mm-151 The existence of unde'nable reals is pretty weird, as was discussed> by Bill Taylor and I a while ago. On the one hand, you can argue that> such things have to exist, by cardinality considerations. But you> can't begin to describe one.Well, what about unde'nable ordinals? It's easy to describe one,e.g., the smallest one. Does that make them less weird, or weirder? =>Or you could tell us what causes v to rotate in the 'rst place.>>There's nothing that causes v to rotate. v is a vector - a mathematical>entity that has direction and magnitude. That's all. It's not a material>thing, so the notion of causation is utterly irrelevant.This is such an appalling expression of pre scienti'c ignorance andmysticism, it leaves me completely speechless. Quite an achievement.You've managed something no one else has. Congratulations. =>Or you could tell us what causes v to rotate in the 'rst place.>>There's nothing that causes v to rotate. v is a vector - a mathematical>entity that has direction and magnitude. That's all. It's not a material>thing, so the notion of causation is utterly irrelevant.> This is such an appalling expression of pre scienti'c ignorance and> mysticism, it leaves me completely speechless. Quite an achievement.> You've managed something no one else has. Congratulations.> What were you supposing? A world with little arrows with feathery tailsattached to everything?Chuck-- ... The times have been, That, when the brains were out, the man would die. ... Macbeth Chuck Simmons chrlsim@earthlink.net>Therefor, it seems to me that there exists a function (indeed, a>function which algebraists subtly draw upon without even realizing>it) that associates with each group it's identity element.What do you mean by function? What the algebraist draws upon is nota function as the word is used in Mathematics.>But I am told that you cannot have a set that contains every group...> so this function's domain is nonsense! Not in a set theory that distinguishes between sets and properclasses. The domain is a proper class, not a set.>Now before you reply Why are you rebutting a claim that nobody made?-- Shmuel (Seymour J.) Metz, SysProg and JOATnot tb@becket.becket.net => Besides, as we have seen, there is no such thing as a function whose> domain is all groups, because the domain of a function is necessarily a> set, and there is no set large enough to contain all groups. We can use> category theory and talk about functors, but the existence of a group> identity does not in any way depend on category theory. Groups had> identities as soon as the concept of a group was formalized, long before> anyone thought up category theory.I would point out that you don't need category theory to make sense ofthis.It's much simpler to use Godel-Bernays set theory, and you can havefunctions--real honest-to-God functions--with domains or ranges thatare proper classes, provided that the actual arguments and values arealways only sets.In GB set theory, you can take the cartesian product of any 'nitelist of classes (proper or not), and a function is just a certainsubclass of that cartesian product. Everything Just Works.And then you can have groups, and a function which maps each group toits identity. The class of groups is a proper class, and the class o'dentities is a proper class, and the function exists just 'ne.Thomas =>> Besides, as we have seen, there is no such thing as a function whose>> domain is all groups, because the domain of a function is necessarily a>> set, and there is no set large enough to contain all groups. We can use>> category theory and talk about functors, but the existence of a group>> identity does not in any way depend on category theory. Groups had>> identities as soon as the concept of a group was formalized, long before>> anyone thought up category theory.> I would point out that you don't need category theory to make sense of> this.That was precisely my point.> It's much simpler to use Godel-Bernays set theory, and you can have> functions--real honest-to-God functions--with domains or ranges that> are proper classes, provided that the actual arguments and values are> always only sets.> In GB set theory, you can take the cartesian product of any 'nite> list of classes (proper or not), and a function is just a certain> subclass of that cartesian product. Everything Just Works.> And then you can have groups, and a function which maps each group to> its identity. The class of groups is a proper class, and the class of> identities is a proper class, and the function exists just 'ne.That's like pointing out that you don't need a bazooka to kill amosquito, because a simple sledgehammer will do.As I said before, the existence of an identity is part of the de'nitionof a group. You don't need anything else at all.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. As I said before, the existence of an identity is part of the de'nition> of a group. You don't need anything else at all.Not to get an identity, but the original question had to do with aset of identities, with functions mapping groups to identities, and Idon't see any reason that those can't be mildly interesting subjectsin their own right.Thomas =>> As I said before, the existence of an identity is part of the de'nition>> of a group. You don't need anything else at all.> Not to get an identity, but the original question had to do with a> set of identities, with functions mapping groups to identities, and I> don't see any reason that those can't be mildly interesting subjects> in their own right.No, the original question had to do with the claim that in order to getan identity, one must implicitly have used such a function.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. As I said before, the existence of an identity is part of the de'nition>> of a group. You don't need anything else at all. Not to get an identity, but the original question had to do with a> set of identities, with functions mapping groups to identities, and I> don't see any reason that those can't be mildly interesting subjects> in their own right. No, the original question had to do with the claim that in order to get> an identity, one must implicitly have used such a function.No. The original question was: Can I de'ne a set of all theidentities of each group? =>As I said before, the existence of an identity is part of the de'nition>of a group. You don't need anything else at all.>> Not to get an identity, but the original question had to do with a>> set of identities, with functions mapping groups to identities, and I>> don't see any reason that those can't be mildly interesting subjects>> in their own right.>> No, the original question had to do with the claim that in order to get>> an identity, one must implicitly have used such a function.> No. The original question was: Can I de'ne a set of all the> identities of each group?I quote the 'rst 16 lines from the posting that began this thread(including the header:>>questions.>>OK, every group has an identity element, right? True by de'nition>>It seems to me that, given a group, that group therefor determines a>unique identity element. (The uniqueness of a given group's identity>element is easily proved)>>Therefor, it seems to me that there exists a function (indeed, a>function which algebraists subtly draw upon without even realizing it)>that associates with each group it's identity element.There is more in the original posting, but the parenthetical comment justabove is what I have been discussing all along. No, it is not true thatalgebraists are subtly drawing upon the existence of such a function inasserting that groups have inverses. Algebraists are drawing on nothingmore than the de'nition of a group in making that assertion.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. There is more in the original posting, but the parenthetical comment just> above is what I have been discussing all along. No, it is not true that> algebraists are subtly drawing upon the existence of such a function in> asserting that groups have inverses. Algebraists are drawing on nothing> more than the de'nition of a group in making that assertion.What started the discussion was Sniz Pilbor's question Is it possiblefor a set to exist which contains all the units of variousisomorphically distinct groups that exist?, in Message ID clari'cation let on that Sniz meant identity when he saidunit, and he wanted the set to have a distinct element for eachisomorphically distinct group.When he was told no, such a set is too big to be a set, he said butisn't there implicit reliance on a function from groups toidentities? You are quite right that in algebra there is no need for such afunction.My point, from the standpoint of set theory, is that there is noproblem in having such a function, even if the range and domain aretoo big to be sets.Thomas =>> There is more in the original posting, but the parenthetical comment just>> above is what I have been discussing all along. No, it is not true that>> algebraists are subtly drawing upon the existence of such a function in>> asserting that groups have inverses. Algebraists are drawing on nothing>> more than the de'nition of a group in making that assertion.> What started the discussion was Sniz Pilbor's question Is it possible> for a set to exist which contains all the units of various> isomorphically distinct groups that exist?, in Message ID clari'cation let on that Sniz meant identity when he said> unit, and he wanted the set to have a distinct element for each> isomorphically distinct group.said identity, not unit. You may be referring to some differentthread, but I am talking about the current one.> When he was told no, such a set is too big to be a set, he said but> isn't there implicit reliance on a function from groups to> identities? > You are quite right that in algebra there is no need for such a> function.> My point, from the standpoint of set theory, is that there is no> problem in having such a function, even if the range and domain are> too big to be sets.But how do you propose to de'ne such a function? Never mind whether thedomain and range are sets or not. How, exactly, do you know that everygroup has an identity?My point has been that you are placing the cart before the horse.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. But how do you propose to de'ne such a function? Never mind whether the> domain and range are sets or not. How, exactly, do you know that every> group has an identity? My point has been that you are placing the cart before the horse.Actually, the set forming the group and the operation are suf'cientto de'ne the identity. That is, a group can perfectly well bede'ned as a structure such that g and * have the followingproperties. This works because the identity is uniquely determinedby the set and the operation.This is less convenient, so we don't do it.You still seem to be mistaking me for someone else. I agreecompletely that we don't need such a function. I don't thinkalgebraists have any use for it, and I don't agree that it isimplicitly necessary.But I still insist that it might be a question of mild independentinterest for set theory.Thomas =>> But how do you propose to de'ne such a function? Never mind whether the>> domain and range are sets or not. How, exactly, do you know that every>> group has an identity?>> My point has been that you are placing the cart before the horse.> Actually, the set forming the group and the operation are suf'cient> to de'ne the identity. That is, a group can perfectly well be> de'ned as a structure such that g and * have the following> properties. This works because the identity is uniquely determined> by the set and the operation.> This is less convenient, so we don't do it.And even if we did, we would still be using the de'nition of a group inorder to de'ne the identity-valued function.> You still seem to be mistaking me for someone else. I agree> completely that we don't need such a function. I don't think> algebraists have any use for it, and I don't agree that it is> implicitly necessary.Yes, we both agree that the function is not necessary, but you keepavoiding the question of whether it is suf'cient. I say it is not.In other words, you seem to think there are two ways to establish theexistence of an identity in an arbitrary group: one way using thede'nition of a group, and one way using an identity-valued functionbut without appealing to the de'nition.I disagree. Both of your methods depend on the de'nition, whether yourealize it or not. Proof: apply your method to semigroups and see howfar you get with constructing your identity-valued function.> But I still insist that it might be a question of mild independent> interest for set theory.L'Hospital's rule is of some interest to analysts, but attempting to useit to evaluate lim_{x->0} (sin x)/x is circular reasoning.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. You still seem to be mistaking me for someone else. I agree> completely that we don't need such a function. I don't think> algebraists have any use for it, and I don't agree that it is> implicitly necessary. Yes, we both agree that the function is not necessary, but you keep> avoiding the question of whether it is suf'cient. I say it is not.I don't care about that question. I think your answer to it isright. I haven't said anything to the contrary.> In other words, you seem to think there are two ways to establish the> existence of an identity in an arbitrary group: one way using the> de'nition of a group, and one way using an identity-valued function> but without appealing to the de'nition.No, I haven't said anything of the kind.> I disagree. Both of your methods depend on the de'nition, whether you> realize it or not. Proof: apply your method to semigroups and see how> far you get with constructing your identity-valued function.My method? What on earth is that? I think that you are very likelyconfusing me with someone else.> But I still insist that it might be a question of mild independent> interest for set theory. L'Hospital's rule is of some interest to analysts, but attempting to use> it to evaluate lim_{x->0} (sin x)/x is circular reasoning.My point, and my only entry to this whole subject, has been on theset-theoritic aspects. => With all respect, sir, I can guess your politics right across the> board. Just for openers, you're a Sierra Club, save-the-whales type.> Gotcha, huh?You're about as far off the mark as it is possible to get. Not that I seethe relevance, but I'm a very conservative, Religious Right type -- notfar removed from what most people would call a fundamentalist (thoughI don't use that label myself). I'm irrevocably opposed to both abortionand gun control, voted for Bush (both of them) and supported the Iraq war(both of them), and certainly do not support the Sierra Club, Greenpeace,PETA, or any other environmentalist or animal-rights group. And no,I don't care to discuss or defend any of those positions in sci.math.(Sorry if that sounds a bit abrupt, but this discussion has already gonepretty far off-topic and I don't want to get drawn in any further.)I also was the kind of kid who grew up reading science 'ction andplaying with chemistry sets, microscopes, slide rules, soldering ironsand telescopes while the other kids were outside playing baseballand football. (To this day I have no interest whatsoever in sports.)So that probably explains why I enjoy technology more for its own sakethan for its applications.-- Wayne Brown (HPCC #1104) | When your tail's in a crack, you improvisefwbrown@bellsouth.net | if you're good enough. Otherwise you give | your pelt to the trapper.e^(i*pi) = -1 -- Euler | -- John Myers Myers, Silverlock-- Wayne Brown (HPCC #1104) | When your tail's in a crack, you improvisefwbrown@bellsouth.net | if you're good enough. Otherwise you give | your pelt to the trapper.e^(i*pi) = -1 -- Euler | -- John Myers Myers, Silverlock = With all respect, sir, I can guess your politics right across the> board. Just for openers, you're a Sierra Club, save-the-whales type.> Gotcha, huh? You're about as far off the mark as it is possible to get. Not that I see> the relevance, but I'm a very conservative, Religious Right type -- not> far removed from what most people would call a fundamentalist (though> I don't use that label myself). I'm irrevocably opposed to both abortion> and gun control, voted for Bush (both of them) and supported the Iraq war> (both of them), and certainly do not support the Sierra Club, Greenpeace,> PETA, or any other environmentalist or animal-rights group. And no,> I don't care to discuss or defend any of those positions in sci.math.You're right as right can be. Taking what you say at face value, whichI do, I was indeed off the mark in that assessment. My apologies. Youalso sound like my kind of guy, for that describes me absent thereligious overtones. I despise political liberals, and I'll let it goat that as well in that most writers are political liberals,enviro-whackos and PETA types. Ursula => I don't use that label myself). I'm irrevocably opposed to both abortion> and gun control, voted for Bush (both of them) and supported the Iraq war> (both of them), and certainly do not support the Sierra Club, Greenpeace,What do you think of this:http://www.deanforamerica.com/site/PageServer?pagename= policy_statement_civilrights_sensiblegunlaws =>> I don't use that label myself). I'm irrevocably opposed to both abortion>> and gun control, voted for Bush (both of them) and supported the Iraq war>> (both of them), and certainly do not support the Sierra Club, Greenpeace,> What do you think of this:> http://www.deanforamerica.com/site/PageServer?pagename=policy_ statement_civilrights_sensiblegunlawsAs I said, I don't want to get drawn any further into this discussionso I'll just say this: I disagree with nearly everything on that page,as I don't consider those laws sensible. And that's all I'm going tosay on the subject here.-- Wayne Brown (HPCC #1104) | When your tail's in a crack, you improvisefwbrown@bellsouth.net | if you're good enough. Otherwise you give | your pelt to the trapper.e^(i*pi) = -1 -- Euler | -- John Myers Myers, Silverlock =>But that's always been the case. We made a lot of money doing>work that our customers didn't want or have to do. What we>didn't do (when we weren't ing idiots) was hide all the>warts under pretty pictures.I'm sorry, WHAT did you say you were doing to the idiots?! =>>But that's always been the case. We made a lot of money doing>>work that our customers didn't want or have to do. What we>>didn't do (when we weren't ing idiots) was hide all the>>warts under pretty pictures.>>I'm sorry, WHAT did you say you were doing it as anadjective and not an action item./BAH =rusin@vesuvius.math.niu.edu (Dave Rusin) said:>>But that's always been the case. We made a lot of money doing>>work that our customers didn't want or have to do. What we>>didn't do (when we weren't ing idiots) was hide all the>>warts under pretty pictures.>>I'm sorry, WHAT did you say you were doing to the idiots?!I *think* he said that he was Oing you'. Still, don't take my wordfor it. I mean, I'm just passing through and all.adios--We lived the dream - P.RidsdaleOh really, Peter? How about We lived the dream and won all? =>rusin@vesuvius.math.niu.edu (Dave Rusin) said:>>But that's always been the case. We made a lot of money doing>work that our customers didn't want or have to do. What we>didn't do (when we weren't ing idiots) was hide all the>warts under pretty pictures.>>I'm sorry, WHAT did you say you were doing to the idiots?!>>I *think* he said that he was Oing you'. Still, don't take my word>for it. I mean, I'm just passing through and all.Nope. De'nition of ing idiot is a person who knows betterbut does it anyway./BAH = With all respect, dear man, you strike me as that type more enamored> with process rather than function. Most of us out here have far better> things to do than screw around for weeks con'guring newsreaders and> the like, even if we were so inclined, which most of us clearly are> not. I suppose we could memorize the phone book, too, but would that> help us communicate our ideas any better?> Some of us prefer to view the forest rather than count the trees down> there. Better view, too. Well, I 'nd the technical aspects of how USENET functions much more> interesting than most of the discussions that take place on it. By the> same token, I am much more interested in the hardware and operating system> software of the systems I administer than in any of the applications> for which they are used. Once I hoped that the growing popularity of personal computers meant> that nearly everyone would learn to think like programmers. It never> occurred to me that, sadly, the opposite would happen: That computers> would be man, that is all 'ne and good, but you'd do well to examine your> thinking here a little more closely. You're seeing the world from a> very narrow vantage point. Technology and inventive genius exist to> serve those who use and take advantage of them, not merely those who> design and invent, otherwise you might just as easily make the> argument that the world was a far better place when mostly car> builders and those who tinkered all day with Model T Fords were out> there driving on the roads. Certainly the roads were safer then, and> that those driving them generally knew their cars inside and out, but> that ignores the fundamental purpose behind that of automobiles, which> is to facilitate transportation. The same exact argument can be made for telephones, television,> airplanes and a whole host of other modern conveniences we now take> for granted and which represent fundamental shifts in the way we> communicate and get around. They were all once the domain of a select> few tinkerers and inventors who had absolutely no idea of what they> were about to unleash on the world. With all respect, sir, I can guess your politics right across the> board. Just for openers, you're a Sierra Club, save-the-whales type.> Gotcha, huh?I think you're entrenching him. He said it was cooler when programmersused Oem. You said it's cooler when people who knew vehicles insideout were the ones driving them.You guys are agreeing. => Shmuel (Seymour Starblade13@Yahoo.com (Starblade Darksquall) said:>>Really though, the bad ones are the lousy English/British.>> The British have a lot to answer for, but so do many other countries.>> French colonial behavior was worse than the British, and you really>> don't want to know what Belgium did. As for slavery, England outlawed>> it well before we did.>> We had as much to do with causing the Great Depression as the English>> did. As to WW I, it was the triumph of diplomacy over sanity; the>> basic cause of the war was a bunch of mutual defense treaties with>> hair triggers.>>Then they gave lands they promised to the Muslims to the Jews>> Actually, they promised the land to both, and were restricting Jewish>> immigration even during the Holocaust.>>They totally messed us up in Vietnam because they didn't help us>>out.>> Indochina was a French colony. Why should the British get involved. We>> were the ones that messed up, 'rst by helping the French get back in>> and second by going in when the French pulled out. We should have gone>> in as Ho Chi Mihn's ally when he invited us...>>*>It is only very rarely that we see this point of view expressed. The >US mistake in Viet Nam was not that we got involved in the war; our >problem was we were on the wrong side.>>Not one in a hundred Americans know that Ho Chi Minh was a great fan >wanted his country free of outsiders. He made many trips to the US, >asking congressmen for help to evict the French.>One cannot reasonably evaluate the decisions the US made there, at the time, without taking into account what was going on in Europe, at the same time. Global politics is not compartmentalized.Mati Meron | When you argue with a fool,meron@cars.uchicago.edu | chances are he is doing just the same => Shmuel (Seymour J.) Metz Starblade13@Yahoo.com (Starblade Darksquall) said:>>Really though, the bad ones are the lousy English/British.>> The British have a lot to answer for, but so do many other countries.>> French colonial behavior was worse than the British, and you really>> don't want to know what Belgium did. As for slavery, England outlawed>> it well before we did.>> We had as much to do with causing the Great Depression as the English>> did. As to WW I, it was the triumph of diplomacy over sanity; the>> basic cause of the war was a bunch of mutual defense treaties with>> hair triggers.>>Then they gave lands they promised to the Muslims to the Jews>> Actually, they promised the land to both, and were restricting Jewish>> immigration even during the Holocaust.>>They totally messed us up in Vietnam because they didn't help us>>out.>> Indochina was a French colony. Why should the British get involved. We>> were the ones that messed up, 'rst by helping the French get back in>> and second by going in when the French pulled out. We should have gone>> in as Ho Chi Mihn's ally when he invited us...>>*>It is only very rarely that we see this point of view expressed. The >US mistake in Viet Nam was not that we got involved in the war; our >problem was we were on the wrong side.>>Not one in a hundred Americans know that Ho Chi Minh was a great fan >wanted his country free of outsiders. He made many trips to the US, >asking congressmen for help to evict the French.>> One cannot reasonably evaluate the decisions the US made there, at the > time, without taking into account what was going on in Europe, at the > same time. Global politics is not compartmentalized. Mati Meron | When you argue with a fool,> meron@cars.uchicago.edu | chances are he is doing just the sameWhat was going on in Europe? And what is meant by Ho Chi Minh wantingto evict the French? What were they doing in there?(...Starblade Riven Darksquall...) =>>Really though, the bad ones are the lousy English/British.>> The British have a lot to answer for, but so do many other countries.>> French colonial behavior was worse than the British, and you really>> don't want to know what Belgium did. As for slavery, England outlawed>> it well before we did.>> We had as much to do with causing the Great Depression as the English>> did. As to WW I, it was the triumph of diplomacy over sanity; the>> basic cause of the war was a bunch of mutual defense treaties with>> hair triggers.>>Then they gave lands they promised to the Muslims to the Jews>> Actually, they promised the land to both, and were restricting Jewish>> immigration even during the Holocaust.>>They totally messed us up in Vietnam because they didn't help us>>out.>> Indochina was a French colony. Why should the British get involved. We>> were the ones that messed up, 'rst by helping the French get back in>> and second by going in when the French pulled out. We should have gone>> in as Ho Chi Mihn's ally when he invited us...>>*>It is only very rarely that we see this point of view expressed. The >US mistake in Viet Nam was not that we got involved in the war; our >problem was we were on the wrong side.>>Not one in a hundred Americans know that Ho Chi Minh was a great fan >wanted his country free of outsiders. He made many trips to the US, >asking congressmen for help to evict the French.>> One cannot reasonably evaluate the decisions the US made there, at the > time, without taking into account what was going on in Europe, at the > same time. Global politics is not compartmentalized. Mati Meron | When you argue with a fool,> meron@cars.uchicago.edu | chances are he is doing just the same What was going on in Europe? And what is meant by Ho Chi Minh wanting> to evict the French? What were they doing in there? Evicting the French simply means telling the French every few years or so that Napoleon was obviously a moron. So they're obviously better advised to do Frenchish things that are within their limited cerebral powers to accomplish, such as buying up some Saudia Arabian or Hong Kong musuem property, and let Viet Nam take care of Viet Nam trees. Since the only quicker death that following a Frenchman to the North Pole is following a Frenchman to a Vietnamese jungle. (...Starblade Riven Darksquall...) = Shmuel (Seymour J.) Metz Starblade13@Yahoo.com (Starblade Darksquall) said:Really though, the bad ones are the lousy English/British. The British have a lot to answer for, but so do many other countries.> French colonial behavior was worse than the British, and you really> don't want to know what Belgium did. As for slavery, England outlawed> it well before we did. We had as much to do with causing the Great Depression as the English> did. As to WW I, it was the triumph of diplomacy over sanity; the> basic cause of the war was a bunch of mutual defense treaties with> hair triggers.Then they gave lands they promised to the Muslims to the Jews Actually, they promised the land to both, and were restricting Jewish> immigration even during the Holocaust.They totally messed us up in Vietnam because they didn't help us>out. Indochina was a French colony. Why should the British get involved. We> were the ones that messed up, 'rst by helping the French get back in> and second by going in when the French pulled out. We should have gone> in as Ho Chi Mihn's ally when he invited us...*It is only very rarely that we see this point of view expressed. The US mistake in Viet Nam was not that we got involved in the war; our problem was we were on the wrong side.Not one in a hundred Americans know that Ho Chi Minh was a great fan wanted his country free of outsiders. He made many trips to the US, asking congressmen for help to evict the French.Our refusal drove him to China and the communist position that he eventually took.The Viet Nam constitution, which was authored by Ho Chi Minh, is patterned after the US constitution.For much more detail, read Schlessinger's book, Ten Thousand madrian@pool-141-158-37-173.phil.east.verizon.net =I know what these functions are, but how are they related?Mike =Take a 3-by-3 grid.Starting in any square, you can place 1 through 9 in the grid so thatconsecutive integers are in adjacent (below/above/left/right)grid-squares, and such that...by some mathematical rule applied to each row and column, the integersin the row/columns, together with the rule applied to the integers(intheir order and independently of integers not in the particularrow/column), produce these integers as output: --------| | | | 248 --------| | | | 236 --------| | | | 10 -------- 68,92,82And, using the same rule, but applied to a 4-by-4 grid, and placing 1through 16 (as above) so as to form a chain of integers, but (here)the 1 and 16 must be adjacent (below/above/left/right), we get thefollowing integers as output:rows:2357122925213315columns:525741892421753What is the mathematical rule, and how are the integers placed intothese grids?Leroy Quet =>Take a 3-by-3 grid.>Starting in any square, you can place 1 through 9 in the grid so that>consecutive integers are in adjacent (below/above/left/right)>grid-squares, and such that...>>by some mathematical rule applied to each row and column, the integers>in the row/columns, together with the rule applied to the integers(in>their order and independently of integers not in the particular>row/column), produce these integers as output:>> -------->| | | | 248 > -------->| | | | 236> -------->| | | | 10> -------- > 68,92,82Leroy, shouldn't the number in the 'rst row be 284 instead of 248?If so, then I have a solution for the 3x3 puzzle, but not for the 4x4one (I suspect my formulation of the mathematical rule generalisesdifferently to 4x4 than yours). -- Erick =>Take a 3-by-3 grid.>Starting in any square, you can place 1 through 9 in the grid so that>consecutive integers are in adjacent (below/above/left/right)>grid-squares, and such that...>>by some mathematical rule applied to each row and column, the integers>in the row/columns, together with the rule applied to the integers(in>their order and independently of integers not in the particular>row/column), produce these integers as output:>> -------->| | | | 248 > -------->| | | | 236> -------->| | | | 10> -------- > 68,92,82 Leroy, shouldn't the number in the 'rst row be 284 instead of 248?> If so, then I have a solution for the 3x3 puzzle, but not for the 4x4> one (I suspect my formulation of the mathematical rule generalises> differently to 4x4 than yours). -- ErickYou are right and right...I double double-checked the numbers, but *still* did not realize I hadexchanged the two digits.And there is a relatively simple rule for the 3-by-3 case, which by acertain generalization can extend to all sequences of n positiveintegers.Leroy Quet the numbers, but *still* did not realize I had>exchanged the two digits.>>And there is a relatively simple rule for the 3-by-3 case, which by a>certain generalization can extend to all sequences of n positive>integers.I'm still at a loss for what the rule is, but I believe I have determinedthe placement of the 4x4 grid. Will you con'rm whether this is correct? 10 11 14 15 9 12 13 16 8 5 4 1 7 6 3 2 -- Erick =Fast ForwardZ: M-theory may be the 'nal proof of the bankruptcy and heuristic exhaustion of the formal-empirical methods of modern physics. On the other hand, under the right interpretation, it might open up new vistas. We'll see.No argument from me on that one! What a double standard eh? -- about hype in science I mean. People are always telling me to connect my theories with experiments and observations. Well that's what I have done more so that anything on NOVA's Elegant Universe although I doconnect my math with their stringy alpha' and indeed I think what I have done inhttp://qedcorp.com/APS/EmergentGravity.pdf is good for Witten & Co I have connected their vaporware more closely to observations of important stuff like the cosmological constant.Z: But the extravagant resort to these multi-dimensional hyperspaces looks very suspicious to me -- regardless of how neatly the Standard Model 'ts into the formalism. Pythagorism run amuck? In any case, Puthoff is not claiming that his PV theory is any kind of fundamentaltheory of gravitation -- just a highly computable working model that might be at least pragmatically justi'ed by some future deeper theory.Not so, I think he claims he has a viable alternative to Einstein.Z: I honestly don't understand why you think you are in direct competition with Hal.Because he got all the money people in the fringe BPP people to think he is on the right path - not that there is a lot of money there. But because of his past top security clearances he has in§uence and access inside USG Black Ops and in fact there is a factional 'ght inside USG right now about all this - more than that I cannot say. So theissue is one of whistle blowing on wasting tax payer money on things that have no chance of working whilst ignoring things that do.....Z: I'm not sure we're on the same page here. But I *am* talking about refutation of Einstein equivalence -- within the framework of canonical GR.space-time. It's complicated but standard in MTW et-al.If ALSO there is TORSION then additional coupling of spinning test Akimov in Moscow says that is a big effect with weapons applications. One guy here who came to ISSO 2000 also said that and he was working on report. Most researcher pooh pooh that. I do not know'rst-hand.String theory is like 2D 'eld theory because the string sweeps out aworld sheet in ordinary space-time rather than the 1D world line. Thisis a great thing because it essentially does away with the in'nitiesCosmological Constant problem, which worries Witten and rightly so.such problems.NO! String theory give bad prediction /zpg = 10^66 cm^-2 when experiment says /zpf = 10^-56 cm^-2 because Witten's strings are only 10^-33 cm as Brian Greene repeats many times in the NOVA vaporware.String theory is no better than local 'eld theory on this issue! Well only a little better, but still 122 Powers of Ten off-target!Witten understands that! They lack my giant vacuum coherent 'eld!http://qedcorp.com/APS/EmergentGravity.docZ: After all - you get an in'nite mass density and in'nite electrical Newtonian gravitational force is in'nite at zero separation of two mass points. The classical electron was a hopeless conundrum even in Lorentz's theory.THIS IS NOT THE PROBLEM....imprecise and ambiguous - goodfor poetry not for physics.Z: Your simple dichotomy between ordinary words and math is a false one IMO. There is ordinary language, there is *technical* and *scienti'c* language, and there is the highly re'ned and abstract language of natural philosophy. Then there is mathematics.If the formal mathematics is to have a well-de'ned physical meaning -- a physical interpretation -- then it must be arrived at and expressed in extra-mathematical technical and philosophical language.Even Einstein had an equivalence principle -- expressed in what you call equations and before he even had a metric tensor representation of the g-'eld. Yet we still don't know what these 'eld equations mean exactly, except in purely formal-empirical terms, since Einstein's equivalence principle is problematic.I do not mean that ordinary language is not useful or important. I meant that it is not enough. Einstein had math to back up his essential points in ordinary language. So far, I am not aware of even ONE math formula to back up any of your key points that you have expressed so far only in ordinary informal language. Am I mistaken here? Please correct me if I missed something. We have been going back and forth on this for almost 2 years now without any relevant math from your corner. Einstein's equivalence principle is classical and the boundary of its domain of validity is fuzzy and problematical, which is part of its greatness like great Art and Poetry. For example the classical Einstein equivalence principle and the quantum Heisenberg uncertainty principle work hand in hand to produce the random micro-quantum Diff(4) covariant additional term /zpf(x)guv(x) in Einstein's local 'eld equation. See John Peacock's Cosmological Physics pp 25-6 for that derivation. Einstein's equivalence principle has a nice mathematical expression in the tetradtransformationFLAT SPACE-TIME = TETRAD (CURVED SPACE-TIME)and inverselye.g.nab = ea^u(P)eb^v(P)guv(P)As far as I can see the math of the point you are making is thatTORSION-FREE CONNECTION = HOMOGENEOUS 3rd RANK TENSOR + INHOMOGENEOUS PIECESo your inertial 'eld is the second piece on RHS.What more is there to be said here? It's in the standard Einstein theory. One can quibble about the informal language attached to this formula, but I think it is a quibble. EEP here also means that locally at event P one can 'nd timelike geodesic frames in which theTORSION-FREE CONNECTION = 0 at P but not in neighborhood of P when tensor curvature =/= 0 at P.torsion 'eld was not considered in Einstein's original theory. But that is a straight forward extension.Einstein's theory guv(P) is from locally gauging the LINEAR TRANSLATIONS inCONFORMAL = DILATION x NONLINEAR SPECIAL TRANSLATIONS x LINEAR TRANSLATIONS x SPACE-TIME ROTATIONSTORSION is local compensating gauge 'eld from SPACE-TIME ROTATIONS.We should LOCALLY GAUGE EVERYTHING! Why stop at a subgroup?The torsion-free connection can probably be split into the homogeneoustensor part + the inhomogeneous part. Indeed I remember that and can quickly look it up. So if that is all you mean, then that is standard Einstein.What then is the point here?Z: That's not it. The decomposition I am talking about is orthogonal to this.I have no idea of what you mean here if you cannot produce a math formula to give the informal sentence meaning.Z: I have explained the point many times. We are separating the inertial and gravitational contributions to the connection 'eld.You have explained nothing to my mind unless there is math to give the words meaning and/or a precise operational gedankenexperiment in sense of the Bohr-Einstein debates. Also, showing how your new insight predicts some new physics and/or explains an important mystery in the old physics is also desired. I gather deformational means Ruvwl curvature tensor =/= 0 at P ?Z: It means the contribution to the connection 'eld (i.e. metricgradients) that results from the deformation of the spacetime manifold, where Ruvwl =/= 0.Transformational is when Ruvwl = 0?Z: It's what you have left when you set Ruvwl = 0. It is obviously still present even when Ruvwl =/= 0 in almost all frames.Fine.Z: OK.I think that is what I said above. It's already there in Einstein's original theory. Nothing new here IMHO.Z: This is really a matter of pure differential geometry, since it holds generally in the abstract, without any speci'c reference to spacetime manifolds.I do not understand what you mean by inertial compensation above.Z: Just think of how inertial and electrical forces interact and howthis is described mathematically in *standard GR*. The EM 'eld is not geometrodynamic, while the pure inertial 'eld (no gravitational sources) is.Ruv = 0 has curved vacuum solutions without ordinary matter Tuv sources.EM 'eld is geometrodynamical in Kaluza-Klein with one extra spacedimension.Z:That's not *standard GR*, JackZ: Are you telling me that Kaluza-Klein is now canonical? Or are you talking about superstring theory?Yes, in sense there is well-de'ned math meaning to their concepts, which is lacking in most of your thesis here unless I have missed something speci'c? I think the 'ctitious or inertial g-force i.e. the metric torsion-free connection for parallel transport in the original 1915 theory is LOCALLY equivalent to a gravity force.Z: Einstein's principle was that a uniform gravitational 'eld is*fundamentally indistinguishable* from an inertial 'eld. That is all in the historical record.Depends what one means by fundamentally.Z: It is quite clear what Einstein meant. He was quite forthcoming onthis. I think it's important to recognize that this is the cornerstone of Einstein's concept of general relativity. The meaning of Einstein's principle is quite unambiguous when placed in context.Fine, but nothing wrong with what Einstein said above except thatphysically we never have a global uniform gravity 'eld.Z: There is nothing wrong with it except that it is almost certainly false as a matter of empirical fact.Yes, but one could imagine a universe like that in terms of the parameters of the theory.Z: Einstein had to pretend that while Riemann curvature distinguishes almost all permanent gravitational 'elds (Eddington, Tolman, Bergmann) from all inertial 'elds, it has no direct physical meaning, at least in the immediate neighborhood of a spacetime point.No, again I think you are mis-interpreting here. If the local curvature is not zero it is not zero in any frame at P. However, its tidal effect at P is ignorable in a small enough neighborhood of P provided:1. Not near a space-time singularity2. Not inside the effective Planck area Lp*^2End of story. It's and approximate statement or a correspondance principle. Einstein was not thinking about Lp^2 = hG/c^3 in 1915, Heisenberg did not do his thing until 1925!Z: As far as I can see Einstein was simply (although understandably) confused about the distinctions between empirical correspondence, formal correspondence, formal analogy, and the literal identity of inertial and gravitational phenomena.Quite possibly, but so what? It's no big deal today unless you can use your new insight to explain why cosmological constant is small, and the true nature of both dark energy and dark matter and also the string structure of lepto-quarks and gauge force bosons etc. As a minor historical point maybe you are correct. I don't know without studying the classic writings more deeply.Z: As far as I can see this approach is a hangover from the fundamentally wrong- headed logical empiricism of the 1920s. How is the MTW argument regarding localized vacuum stress-energy based on theEEP any different from arguing that since the speed of an object cannot be measured at an instant, the speed of the object has no physical meaning at an instant? Hence, as Zeno might argue, motion is impossible, since at each instant the object cannot be said to be moving? We enlightened moderns have the differential calculus. We are supposed to know better. Eddington pointed out in 1922 that there is no rational foundation for insistence on such a sweeping universal assumption (Einstein equivalence) -- that it is merely a conjecturethat is subject to empirical test and that it is a mistake to assume that the hypothesis *must* be true. And whether it is or is not is as far as *formal-empirical* GR is concerned a purely empirical matter.In other words, it was merely Einstein's guess. A sweeping extrapolation. A bold hypothesis. Based on what we know now, as a general law of nature, quite possibly a huge RED HERRING. This was later reiterated by Feynman in his Lectures on Gravitation, where he actuallymade some gentle fun of Einstein (or at least Einstein's more fanatical followers). Clearly, we know there is a formal-empirical *analogy* between gravitational and inertial 'elds, but only a partial one (Eddington 1922). But a partial analogy -- short of identi'cation-- is a perfectly adequate basis for a weaker physical interpretation of the so-called EEP as technically formulated by Wheeler et al. that does not imply the identity of gravitational and inertial phenomena.That's only an idealization.Z: The EEP is an idealization. But the EEP does not capture Einstein equivalence without an additional layer of interpretation.IMO EEP amounts to an *ad hoc* stratagem whereby, in order to appear to save the Einstein equivalence hobbyhorse, the fundamental distinction between equivalence as identity, and equivalence as mere local correspondence with §at-spacetime SR, is systematicallyobfuscated, and a minimal agnostic epsilon-delta type technical formulation is misleadingly represented as somehow capturing the content of Einstein's principle (hence the misnomer EEP). It doesn't. It is *consistent* with it, but it does not capture the full content of Einstein equivalence. That is why I call the MTW development of canonical GR a shell game. You have to keep your eyes on that pea.What they do in Gravitation in certain important contexts is to tacitly attach the additional layer of Einsteinian interpretation in their supposed proof of the non-locality of vacuum stress-energy.The physical 'eld is supposed to be eliminated (i.e. annihilated) at a point in a free-fall frame. But that is Einstein equivalence, and not merely EEP. If Einstein equivalence is empirically false, then it can hardly be invoked as the theoretic basis for the of'cial interpretation of the GR formalism, of the EEP, or as the basis for an argument against localized vacuum stress-energy, as MTW would have it.However, under a suitable reinterpretation, the entire general-covariant formal machinery of canonical GR still works 'ne. But at the same time, the reinterpreted theory may point in very different directions as correspondence relation between the two theories. That this very bold Einstein concept of gravitational-inertial equivalence historically led Einstein to the GR tensor 'eld equations in the manner of a *heuristic guide*, or that Einstein himself may never have explicitly abandoned his bold hypothesis, are neither here nor there as far as the contemporary objective critical discussion of the subject is concerned. IMHO. However, this was all pointed out by Eddington and von Laue in the early 1920s. Too bad M, T, and W apparently ignored them.Tidal differences in the g-force between P and P + dP means curvaturei.e. real gravity as opposed to simulated gravity.Z: Yes, exactly. That is what is meant by a permanent or intrinsicgravitational 'eld.Fine, so what's the problem?Z: The problem is the GR de'nition of vacuum stress-energy, the question of its covariant formal representation, and the question of its localizability -- as I think you know.Again your point here is only interesting if you say there should be more terms inGuv + /zpfguv = -alpha'Tuvalpha' = Ed Witten's inverse string tension (h = c = 1 convention).i.e. if you say there is some kind of power series in alpha'^n with n factors of Guv?Then you have something interesting. Otherwise your point is trivial becauseLOCAL CLASSICAL GEOMETRIC VACUUM STRESS-ENERGY DENSITY TENSOR = alpha'^-1Guv = Tuv(Geometry)LOCAL MICRO-QUANTUM RANDOM ZERO POINT VACUUM STRESS-ENERGY DENSITY TENSOR = alpha'^-1/zpfguvTherefore Einstein's local geometrodynamic 'eld equation is:Sum off all local stress-energy density tensors from classical geometry + random virtual zero point quantum §uctuations + matter + coherent virtual near 'eld + radiation = 0When no torsion and no hyperspace violations of metricity then we have a simple situation from the Bianchi identities that the 4-covariant divergence of the classical geometry stress-energy density currents locally vanish if the vacuum is NOT exotic, but NOT OTHERWISE!Z: Again, you are reverting to your straw man here according to which I am supposed to be 'nding a technical problem with Wheeler's minimal agnostic technical statement of the so- called EEP. I'm not -- except that it is only valid at a spacetime point.As every School Boy knows I suppose -- at least at Cal Tech. :-)Z: But if you want to glimpse part of what I'm getting at, just exchange the epsilon and the delta in Wheeler's formulation of EEP. For any given 'nite neighborhood of a spacetime point, we can in (GR) principle always construct a gravitometer that is suf'cientlysmall and sensitive to detect the effects of non-vanishing Riemann curvature around that point, regardless of the state of motion of the object. All inside Einstein's famous elevator. This turns EEP' on its head. It turns out (and I didn't know this when I 'rst got onto it) that the position I am advancing here is essentially Eddington's as set out in 1924. At that time he viewed Einstein equivalence as heuristic and tentative in character, and not as a fundamental principle. I say he was right on the money. This is the view that was later echoed by Bergmann, Synge, and others. EEP as technically formulated by Wheeler is 'ne -- but it is consistent with either interpretation (Einstein's or Eddington's).So it seems your point is one of the history of relativity on howEinstein's ideas evolved.Z: You don't seem to see that this entails a profound shift in the physical meaning of the GR 'eld equations, and that this means that *we do not have actual general relativity*, regardless of the impressive empirical accuracy of standard GR.You lost me again.Z: If we do not have actual general relativity, then we have not in fact *explained* the equality of gravitational and inertial mass, as Einstein thought he had. We have simply *assumed* it.Again you are too subtle for me here. The crux here is simply thatlight rays move on null geodesics, and nothing moves on spacelike geodesics in torsion-free space-time. You cannot have light, you cannot have anything move on a timelike non-geodesic unless there are charged physically if there were no electric charges. This already shows that gravity must emege from electromagnetism. No charges no weight!Z: The term general relativity, like EEP, is thus in that case a misnomer. In the MTW development of GR it amounts to an elaborate bait-and-switch routine. It also opens up a prospect for the resurrection of a suitably re'ned neo-Lorentzian concept of a non-material aether (physical yet non-material medium of propagationacross the vacuum) to be sharply distinguished from spacetime as a void. Under this model, it is the *physical disturbance* of this aether by the presence of matter that causes deviations from straight-line motion.Less words more math would help clarity here.Z: If we don't actually have *general* relativity, then we don't have relativity, period -- since that implies and demands the physical relativity of *all* motion (A. Einstein). No Einstein equivalence, no general relativity. This *according to Einstein's own classic arguments*.This is more a legal argument then a physics argument. :-)Z: This is IMO profoundly iconoclastic and could have deep implications for the further development of gravitational theory. But the logic is inescapable IMO.Depends what you mean by logic. :-) Is renormalization theory for before and why should it now? Look at Niels Bohr as a good example. :-)I do not see however how this will lead to new physics today unless youmean that addition torsion local gauge 'eld and possibly local gauge 'elds from ALL of the conformal group will modify EEP which is only based upon the 4-parameter translation group of the 15 parameter Conformal Group for Minkowski space-time.Z: I am not trying to modify EEP. I am simply proposing an alternative interpretation to those based on Einstein equivalence. The alternative interpretation points to a very different correspondence model betweenstandard GR and a deeper theory of gravitation. It may hold some important clues to how the analogical relationship between physical gravitation and mechanical inertia, and the basis for weak equivalence (strict proportionality of gravitational and inertial mass) will beexplained in the deeper theory -- which will presumably be some kind of quantum 'eld theory of the gravitational vacuum.I don't see how without speci'c toy models of gedankenexperiments and/or mathematics. I refer to the paper by Utiyama I think in mid-60's also Kibble's later paper in which the general relativity principle is rederived as a kind of local Yang Mills gauge principle in the curved space-time base space of the 'ber bundle where the 'ber is the U(1)SU(2)SU(3) or its GUT internal symmetry generalization. Roughly, the gauge forces are in the principle bundle with unstable globally §at space-time as a coset space mod the internal symmetry subgroup of the total group and the lepto-quarks are the associated vector bundle. One then does the same trick again inside the coset space whose symmetry group is the Conformal Group.Z: Fine. This was also Feynman's approach. He also alluded to gauge symmetries as the basis for EEP *by way of formal correspondence* with standard GR.Yes, that is how everyone in theoretical physics today thinks about it.Z: Does this gauge symmetry of the underlying Yang-Mills 'eld imply that gravitational and inertial 'elds are, physically speaking, literally one and the same phenomenon?I do not understand your question unless you give the math.Connection = Tensor + non-TensorReal gravity is from tidal gradients of Tensor part of ConnectionConnection = 0 in any LIF.g-FORCE = ConnectionIn LIFTensor g-force + non-Tensor g-force = 0So that's compensation at g-force level.Tidal force is the derivative of g-Force!i.e. f(P) = 0 but df(P)/dx^u =/= 0 in LIFZ: If not, then such theories are inconsistent with Einstein equivalence -- although perhaps not with the so-called EEP in its most agnostic formulation.You lost me.was Einstein's. It is inconsistent with Eddington's as stated in Mathematical Theory of Relativity. MTW seem to use both, which strikes me as an example of Bohrian complementarity -- AKA speaking with forked tongue -- in the context of spacetime physics. That is a very bold hypothesis, as Feynman pointed out on many occasions. But it is at the core of Einstein's concept of general relativity, as Einstein himself consistently emphasized (speci'cally to von Laue). Of course, this was later formulated as a local frame, together with our ability to rendertidal effects negligible by going to a suf'ciently small neighborhood. This makes it look on the surface like the Einstein principle is still valid -- hence the misleading acronym EEP.Forget what Einstein allegedly thought in his early days.Z: Jack, this was integral and indispensable to Einstein's idea ofgeneral relativity. So, if you forget about this -- and also Pauli's entire 1921 exposition of GR -- you then have general relativity *without actual general relativity*, as I said early on.I mean, this is a historical point about the initial immatureconception of relativity that got further re'ned into the modern ideas launched in MTW.Z: No, it means that there is in fact no such thing as general relativity. That is a very profound shift of interpretation IMO.All we really have now is *general covariance* and a tensor representation of the gravitational 'eld, and EEP for empirical correspondence with SR.That's good enough.Z: Even Einstein eventually admitted that general covariance in and of itself is empty of physical content (see Autobiographical Notes).Common knowledge.Z: Looks like I was right.But if you are willing to drop this and hew to a consistentnon-Einsteinian interpretation of EEP, then 'ne. But then, the MTW argument against localized vacuum gravitational stress-energyfalls apart (though of course that does not in itself mean there areno other valid objections).The only way you can attack MTW there is to say that their initialassumption that the localized vacuum tensor is quadratic in the connection is a Straw Man, i.e. not complete.Z: Here you are ignoring, or not understanding, my proposal for a canonical local decomposition of the connection 'eld, which I contend avoids all these dif'culties even within the existing GR formalism with its uni'ed abstract metric.like I did above. That there is another form based only on the nonlinear products of the curvature tensor but that would change the 'eld equation from (neglecting zero point /zpfguv)Guv = -(8piG/c^4)TuvtoGuv + Nonlinear products of 4th rank curvature tensor = -(8piG/c^4)TuvThe extra terms are a power series in Lp^2 = hG/c^3they may be there, but are too small on the macro-scale.Is that what you mean?Z: I don't think so. I am talking about a local decomposition of the standard Christoffel connection.Like I showed above - standard stuff. So what? I cannot understand really what you mean until I see formal statements in math that pin down the ambiguities of ordinary language.Z: OK. Of course this has to be done.I think I did it above. This should not take years to do.Z: I gave you a formal expression some time ago but you apparently ignored it.Z: This is principally a matter of proper interpretation of the metric gradients -- even in the abstract context of pure differential geometry... which breaks down when scale ~ Lp* and which emerges from local giant vacuum coherent wave.Z: On the physical level, it is tied to a close analysis of exactly what it means to mathematically meld physical time into a Riemannian spacetime manifold, and precisely how to properly interpret the local transformational properties of the connection 'eld on a curved (i.e.deformed) Riemannian manifold.You lost me without the math.Z: Einstein may simply have gone wrong there -- a victim of his own wishful thinking -- regardless of his impressive heuristic success in arriving at the GR 'eld equations.I crave heuristic success! :-)This is why I feel uneasy about Bohr's reliance on ordinary language inthe quantum reality problem.Z: This is a complex issue that I don't really have the time to get into here. But I do agree that Bohr's insistence on the irreducible use of ordinary language and common sense concepts in describing the results of experiments is very dubious. At the same time I don't think this means that the only satisfactory language for discussion and analysis of the problems of QM is formal mathematics. I would say that this approach simply avoids the entire problem of the proper interpretation of the QM formalism. I believe this was Bohm's view.Which is what I originally argued: the bare EEP does not establishthat the gravitational energy density must vanish at a point, or that its components depend upon the frame of reference in a non-covariant manner. It only requires that the net measurable combined gravitational and inertial forces vanish at a point in some coordinate system. To get the true gravitational stress-energy, we simply ignore theinertial contribution -- that's all. Eddington himself explicitly states that in GR the inertial 'eld has a stress-energy that is frame-dependent and represented by a non-tensor. But this is a *'ctitious* stress-energy, unless you believe in Einstein equivalence *as originally stated* -- which it now appears that you don't.He was perhaps a bit confused whilst the theory was immature.The point is that it's coherent conceptually today in the form MTWhave.Z: I cannot agree. See above. This is a *real interpretive dichotomy* at the most fundamental level. Now you could say somethinglike this about Schroedinger, who really thought he had a wave theory in the classical sense -- but later had to give this up for a number of reasons. Einstein never explicitly abandoned equivalence and true general relativity. Not even in his Autobiographical Notes, which is just about his last word on the subject.You cannot render tidal effects negligible in the approach to asingularity until effective Planck scale is reached. That scale may not be 10^19 Gev after all. It may be 1 Gev?Z: That may well be the case, but this is not part of canonical GR. No doubt a deeper theory, if it ever 'nally comes, will answer such questions.Ed Witten thinks that's M-theory. It's now on NOVA! I am beginning toread Witten. I am getting a little uneasy about all this duality stuff in string theory because it is beginning to remind me of my debate with Hal Puthoff on his use of isotropic r vs. curvature rin the SSS model. This debate is described in my Dec 2002 book Space-Time and Beyond II.Z: M-theory may be the 'nal proof of the bankruptcy and heuristic exhaustion of the formal-empirical methods of modern physics. On the other hand, under the right interpretation, it might open up new vistas. We'll see.No argument from me on that one! What a double standard eh? -- about hype in science I mean. People are always telling me to connect my theories with experiments and observations. Well that's what I have done more so that anything on NOVA's Elegant Universe although I doconnect my math with their stringy alpha' and indeed I think what I have done inhttp://qedcorp.com/APS/EmergentGravity.pd's good for Witten & Co I have connected their vaporware more closely to observations of important stuff like the cosmological constant.Z: But the extravagant resort to these multi-dimensional hyperspaces looks very suspicious to me -- regardless of how neatly the Standard Model 'ts into the formalism. Pythagorism run amuck?My debate with Puthoff was that he was misinterpreting the physics notrealizing that the expansion of space inside a critical radius was an illusion of not realizing what the coordinate patch was in the curved differential manifold.Z: OK.Matt Visser makes this clear in Lorentzian Wormholes in the context of Kruskal coordinates. There is a kind of duality there withr' = r*^2/rbut r' and r are both OUTSIDE the horizon. Puthoff and Ibison makethe conceptual error that r' is INSIDE the horizon! Actually they have no horizon because of their exponential, but they have a critical min turning point radius that plays a similar role.Z: Couldn't this simply be the result of a mathematical ambiguity?No, good books like Matt Visser's Lorentzian Wormholes are good on this. I don't think Puthoff and Ibison ever really read that book or pondered its meaning if they did.Z: In any case, Puthoff is not claiming that his PV theory is any kind of fundamental theory of gravitation -- just a highly computable working model that might be at least pragmatically justi'ed by some future deeper theory.Not so, I think he claims he has a viable alternative to Einstein.Z: I honestly don't understand why you think you are in direct competition with Hal.Because he got all the money people in the fringe BPP people to think he is on the right path - not that there is a lot of money there. But because of his past top security clearances he has in§uence and access inside USG Black Ops and in fact there is a factional 'ght inside USG right now about all this - more than that I cannot say. So theissue is one of whistle blowing on wasting tax payer money on things that have no chance of working whilst ignoring things that do.I am wondering if Witten, Greene & Co are making a similar conceptualerror in that really they ignore the physics INSIDELp*^2 which G.E. Volovik in Universe in a Helium Drop says isessential for solving the smallness of the CosmologicalConstant problem. It's like in condensed matter physics not goinginside the unit cell of the crystal lattice. If you do that youwill get a zero point energy for phonons that is much too large! Thisis Volovik's insight.String theory is like 2D 'eld theory because the string sweeps out aworld sheet in ordinary space-time rather than the 1D world line. Thisis a great thing because it essentially does away with the in'nitiesCosmological Constant problem, which worries Witten and rightly so.such problems.NO! String theory give bad prediction /zpg = 10^66 cm^-2 when experiment says /zpf = 10^-56 cm^-2 because Witten's strings are only 10^-33 cm as Brian Greene repeats many times in the NOVA vaporware.String theory is no better than local 'eld theory on this issue! Witten understands that! They lack my giant vacuum coherent 'eld!http://qedcorp.com/APS/EmergentGravity.docZ After all - you get an in'nite mass density and in'nite electrical Newtonian gravitational force is in'nite at zero separation of two mass points. The classical electron was a hopeless conundrum even in Lorentz's theory.THIS IS NOT THE PROBLEM.There are analogies of string theory with lattice spin Ising modelswhich have a duality relating a T theory to a 1/T theory in a duallattice.Witten introduces the famous alpha' as basically a new stringfundamental constant. He does not seem to connect it to the Salamgravity I worked on in 1973.Z: Yet more knobs and dials. Is any of this really physics? Can this kind of theory really be said to predict anything? Other than in the *ad hoc* formal manner of abstract mathematical description? I'll see if I can comment on the stuff below after I have looked at Witten.Using his h = c = 1 units. Witten's alpha' is essentially an effective'eld Planck area. If we believe Susskind's world hologram we havealpha' = Lp*^2 = Lp^4/3L^1/3at scale LIf we choose L = c/Ho in a kind of Mach Principle of large scalein§uence on small scaleHo = HubbleLp* ~ 1 fermiThe problem with this is the time dependence in H(t) where Ho is thepresent epoch value.Note, in Witten's conventions, energy is 1/LengthThereforealpha' is the universal Regge slope, which for hadronic resonance hasalpha' ~ (1 fermi)^2Quantized spin of resonance = alpha'(Energy of resonant peak)^2 +interceptalpha' is reciprocal string tension since Energy/Length ~ 1/Area in theh = c = 1 convention used by Witten & Co.In my theory/zpf = (alpha')^-1[(alpha')3/2|Vacuum Coherence|^2 - 1}Einstein's gravity emerges fromguv = (Minkowski)uv + (alpha'){Goldstone Phase of VacuumCoherence)(,u,v)}Z: So this seems to map directly over to some bi-metric version of GR.No I do not see that at all. The SUM on RHS is not bimetric anymore than 2 = 1 + 1 is in reality a pair of two 1's with independent parallel existences.Z: You have a §at Minkowski background with a Lorentz metric, with inertial 'elds conceived as artifacts of non-linear spacetime coordinate transformations, PLUS a *physical metric* describing gravitational phenomena that is directly related to your BEC Goldstone phase. Am I right?Yes, but it is only the sum that is physical. I do not see two coexisting independent metrics apart from locally §at tangent bundle idea of standard GR with tetrad map between LIF geodesic 'ber and non-geodesic LNIF base local framesZ: If so, then this is NOT Einstein's gravity. It is *Eddington's* gravity. This was also Feynman's general approach in his Lectures on Gravitation.It is BOTH! I haveGuv + /zpfguv = alpha'TuvZ: As I said, I think your task is going to be a lot easier, as far as correspondence with GR is concerned, under my proposed alternative interpretation of the EEP. You cannot simply sweep all these problems under the carpet emergence IMO.anholonomic torsion 'eld potential = (alpha'){Goldstone Phase ofVacuum Coherence)[,u,v]The O(2) internal symmetry of this complex numbered scalar VacuumCoherence local 'eld implies 1D string topological defects in 4Dspacetime as a rigorous theorem in the text books.Z: OK.More generalized models of O(N) hypercomplex numbered MACRO-QUANTUMVACUUM More is different (P.W. Anderson) coherence order parameterswill give the brane world topological defect generalizations of thesestrings that should also have torsion on the microscale.Z: OK. The most from the least. BTW, how does your theory explain mechanical inertia?Exactly as in Wheeler's book Geometrodynamics with Mass withoutmass except now I have G* = 10^40 G(Newton) at the fermi scale.Z: OK. I'll have a look.I started working on Wheeler's book Geometrodynamics in 1966. Wheeler spoke at UCSD frequently then. The characteristic rest mass of the spatially extended lepto quark of Charge without charge rotating with Spin without spin ism = e^2/zpf^1/2 = e^2/Lp* = e^2(alpha')^-1/2because Vacuum Coherence -> inside the Type II superconductorquantized §ux vortex vibrating string exotic vacuum dark mattercore with ends pinned to the 3Dim brane world we are stuck on like EdAbbott's Flatlanders if the basic Witten & Co ideas are on righttrack.Z: So in your theory, inertial effects result from the physical interaction of matter, conceived as branes, with the quantum vacuum, conceived as a virtual BEC?BRANES emerge FROM virtual BEC. Strings emerge from virtual O(2) BEC which is only low energy long-range limiting case of shorter-scale O(N) BEC in some kind of O(N') or G(Mystery) group hypercomplex number generalization of Einstein's real space-time continuum.Z: Say bye bye to Mach's principle.Not ifLp*^2 = Lp^4/3(c/Ho)^2/3which has a problem however.These 1 Dim strings vibrate in the extra boson space dimensions and theextra fermion supersymmetry matrix space-dimensions forming theCalabi-Yau space generalization of the Kaluza-Klein hyperspace of the1920's.Z: OK. But it only takes one physical effect that is not locallynegligible in this sense to blow out Einstein equivalence.Einstein equivalence is only a classical weak 'eld approximation oryour correspondence principle in the informal sense for the zerotorsion limit.Z: I'm not sure exactly what you mean here. Einstein thought it heldwithout restriction. Looks like you don't agree.I am not sure without doing a careful look. In any case, of coursethere have been subtle modi'cations or re'nements of Einstein's early thinking. These are small corrections so to speak. Only minor clari'cations of his great insights.Z: This is simply not the case, Jack. What I am talking about is a profound counter- revolutionary paradigmatic shift back to some kind of an aether, conceived as a non-material yet physical medium of propagation across the physical vacuum.Z: So it is precisely Einstein's original insight -- that both gravitation and inertia could be jointly reduced to a distortion of an abstract metric in an absolute void, without reference to any physical medium of propagation -- that is in question here. Look, Einstein was a wonderful man and a creative genius, but business is business.Not according to Evan Harris Walker and Einstein's 'rst wife. Music from OThe God Father plays in background. :-)Z: We need to move forward. Let's not be too sentimental about this.There is nothing revolutionary in the distinctions you propose here that I am able to understand at least.Z: Then perhaps -- and I don't say this lightly -- you don't really understand Einstein. You don't seem to realize that you have in fact abandoned his theory of general relativity. Quite rightly, IMO, since THERE IS NO GENERAL RELATIVITY.There you go again sounding like Brian Greene on NOVA! ;-)Z: That is a lot more than a mere detail of history. That can hardly be described as a slight adjustment or re'nement to Einstein's original insight.You lost me. I am only a humble post-Quantum non-mechanic.Z: It is in fact a wholesale *abandonment* of Einstein's original insight, which is now demoted to the status of a mere heuristic tool -- mere scaffolding to be discarded once the cathedral is built, in favor of more solid and durable buttressing that is more in keeping with the 'nal architecture.I am not sure what happens when there is torsion-spincoupling. It can break down for a variety of reasons.Z: Exactly -- you're not sure. The fact is it's anybody's guess and isultimately an empirical question.Not quite - there is a lot of work in the published literature - it'sonly my personal lack of knowledge here I allude to.Z: I'm not sure we're on the same page here. But I *am* talking about refutation of Einstein equivalence -- within the framework of canonical GR.space-time. It's complicated but standard in MTW et-al. If ALSO there is torsion 'elds.Akimov in Moscow says that is a big effect with weapons applications. One guy here who came to ISSO 2000 also said that and he was working on report. Most researcher pooh pooh that. I do not know 'rst-hand.Z: Yet Einstein thought he was completely sure, and said so. That's whyFeynman made fun of him in Lectures on Gravitation.Again this is very minor compared to what is happening now and what I am talking about above in relation to Witten & Co.Z: See above. It changes the entire meta-theoretic relationship between GR and the deeper 'eld theories of gravitation. It profoundly changes our understanding of the vacuum and its relationship to gravitational and inertial phenomena.Show me how in detail. I do not have time to absorb all your points below. Later.Z: OK. = I am a newbie in Galois Field. I wondoned that the relationship betweenthe codewords and generator polymial? I want to know that how to get ageneratorpolynomial in matlab?Yang Jun =Let b(1) = 1;and for k >= 2,b(k) = x *sum{j|k, j= 2, b(k) = x *sum{j|k, j coef'cients? B(r) (or analytical continuation) has a pole at r = R,> where zeta(R) = 1 + 1/x.> So, is the sequence {b(j)} = O(j^(R-1)) (just guessing) or something> else based upon R? Also, 'nally, an obvious but curious fact: If x = 1/zeta(q), for a FIXED q,> then B(q) = zeta(q) itself. Leroy> Quet Jeroen =[First, I am glad that Jeroen's reply contains all of my originalmessage, since the original message did not appear on Math Forum atleast.] As for my apparent error: You are forgetting *one* little thing, ...that b(1) always = 1, whatever x is.;)Leroy Quet I don't get it exactly, must be because I'm not a mathematician and can> hardly grasp what you're doing :) Please see my remarks between the> lines. Let b(1) = 1; and for k >= 2, b(k) = x *sum{j|k, j (Sum is over positive PROPER divisors of k.) Let B(r) = sum{k=1 to oo} b(k)/k^r, So if x=0 then B(r)=0, because b(k)=0 > for those r's where the sum converges. Then B(r) = 1/(1 +x -x *zeta(r)), So if x=0, then B(r)=1. This does not agree with B(r)=0 from a few lines> earlier? > where zeta(r) is Riemann zeta function. So, a few questions: Each b(k) is a polynomial in terms of x. What is closed form for the> coef'cients? B(r) (or analytical continuation) has a pole at r = R,> where zeta(R) = 1 + 1/x.> So, is the sequence {b(j)} = O(j^(R-1)) (just guessing) or something> else based upon R? Also, 'nally, an obvious but curious fact: If x = 1/zeta(q), for a FIXED q,> then B(q) = zeta(q) itself. Leroy> Quet = [First, I am glad that Jeroen's reply contains all of my original> message, since the original message did not appear on Math Forum at> least.] > As for my apparent error:> You are forgetting *one* little thing, ...That's hardly a Olittle thing' I overlooked , but more a capitalblunder... :( that b(1) always = 1, whatever x is.> ;) Leroy Quet> I don't get it exactly, must be because I'm not a mathematician and can> hardly grasp what you're doing :) Please see my remarks between the> lines.>> Let b(1) = 1;>> and for k >= 2,>> b(k) = x *sum{j|k, j> So if x=0 then b(k)=0.> (Sum is over positive PROPER divisors of k.)>> Let B(r) = sum{k=1 to oo} b(k)/k^r,>> So if x=0 then B(r)=0, because b(k)=0> for those r's where the sum converges.>> Then B(r) =>> 1/(1 +x -x *zeta(r)),>> So if x=0, then B(r)=1. This does not agree with B(r)=0 from a few lines> earlier?> where zeta(r) is Riemann zeta function.>> So, a few questions:>> Each b(k) is a polynomial in terms of x. What is closed form for the> coef'cients?>> B(r) (or analytical continuation) has a pole at r = R,> where zeta(R) = 1 + 1/x.> So, is the sequence {b(j)} = O(j^(R-1)) (just guessing) or something> else based upon R?>> Also, 'nally, an obvious but curious fact:>> If x = 1/zeta(q), for a FIXED q,> then>> B(q) = zeta(q) itself.>> Leroy> Quet>> Jeroen =Error indicated where it occurs: I don't get it exactly, must be because I'm not a mathematician and can> hardly grasp what you're doing :) Please see my remarks between the> lines. >Let b(1) = 1;>>and for k >= 2,>>b(k) = x *sum{j|k, j So if x=0 then b(k)=0.Except that b(1) = 1 for all x. >>(Sum is over positive PROPER divisors of k.)>>Let B(r) = sum{k=1 to oo} b(k)/k^r, > So if x=0 then B(r)=0, because b(k)=0No - if x=0, then B(r) = 1, since b(0)=1. >>for those r's where the sum converges.>>Then B(r) =>>1/(1 +x -x *zeta(r)), > So if x=0, then B(r)=1. This does not agree with B(r)=0 from a few lines> earlier? >>where zeta(r) is Riemann zeta function.>>So, a few questions:>>Each b(k) is a polynomial in terms of x. What is closed form for the>>coef'cients?>>B(r) (or analytical continuation) has a pole at r = R,>>where zeta(R) = 1 + 1/x.>>So, is the sequence {b(j)} = O(j^(R-1)) (just guessing) or something>>else based upon R?>>Also, 'nally, an obvious but curious fact:>>If x = 1/zeta(q), for a FIXED q,>>then>>B(q) = zeta(q) itself.>>Leroy>>Quet > Jeroen =what's wrong with the TI-89 calculator?For integration( e^(ax) ) with respect to xS(e^(ax),x)the TI-89 answers: e^(ax)*xBut my book and www.quickmath.com say: e^(ax)/aIs the TI-89 wrong? Or can somehow both be right?Confused,Andi =>For integration( e^(ax) ) with respect to x>S(e^(ax),x)>the TI-89 answers: e^(ax)*xIf the TI-89 reads ax as a single variable, then integrating withrespect to x would make ax, and therefore e^ax, constant. The TI's answerfollows immediately.Try entering e^(a*x) instead. The only reason I guess this to be theissue is because Mathematica handles things the same way.Doug =Doug Norris scribbled the following:>>For integration( e^(ax) ) with respect to x>>S(e^(ax),x)>>the TI-89 answers: e^(ax)*x> If the TI-89 reads ax as a single variable, then integrating with> respect to x would make ax, and therefore e^ax, constant. The TI's answer> follows immediately.> Try entering e^(a*x) instead. The only reason I guess this to be the> issue is because Mathematica handles things the same way.The TI-89 supports multi-letter variables. Therefore it understands axas just that, ax (to rhyme with a tool for chopping 'rewood). Tomake it realise it's supposed to be a multiplied by x, you have to typea*x.The CASIO CFX-9970G, which does not support multi-letter variables,would regard AX and A*X as identical.-- /-- Joona Palaste (palaste@cc.helsinki.') ------------- Finland ---------- http://www.helsinki.'/~palaste --------------------- rules! --------/The obvious mathematical breakthrough would be development of an easy way tofactor large prime numbers. - Bill Gates => what's wrong with the TI-89 calculator?>> For integration( e^(ax) ) with respect to x>> S(e^(ax),x)>> the TI-89 answers: e^(ax)*x>> But my book and www.quickmath.com say: e^(ax)/aThat's a correct antiderivative.> Is the TI-89 wrong? Or can somehow both be right?My guess (since I'm not familiar with the TI-89) is that it's thinking ofax as a single entity, constant with respect to x. If that's the case,then its answer is correct, although it is not answering the question youwant it to answer. (Perhaps you need to type a space between the a andthe x.)David =geschrieben:>> what's wrong with the TI-89 calculator?>> For integration( e^(ax) ) with respect to x>> S(e^(ax),x)>> the TI-89 answers: e^(ax)*x>> But my book and www.quickmath.com say: e^(ax)/a>> That's a correct antiderivative.> Is the TI-89 wrong? Or can somehow both be right?>> My guess (since I'm not familiar with the TI-89) is that it's thinking of> ax as a single entity, constant with respect to x. If that's the case,> then its answer is correct, although it is not answering the question you> want it to answer. (Perhaps you need to type a space between the a and> the x.)the x. And it gets the right result now. Great!!!Markus =Andreas Schmidt grava .88 la saucisse et au marteau:> the TI-89 answers: e^(ax)*x> But my book and www.quickmath.com say: e^(ax)/a> Is the TI-89 wrong? Or can somehow both be right?Yes, if x = 1/a-- Nicolas, what ? =I've forgotten the proof for inverses in a ring of integers mod n. Cansomeone remind me why inverses => I've forgotten the proof for inverses in a ring of integers mod n. Can> someone remind me why inverses only exist for m 1 then every integer multiple of m will also be a multiple of d, and when you reduce that integer multiple of m mod n by subtracting a multiple of n you will be subtracting a multiple of d from a multiple of d, so you will get a multiple of d, so you won't get 1.-- = I've forgotten the proof for inverses in a ring of integers mod n.>> Can someone remind me why inverses only exist for m 1 then every integer> multiple of m will also be a multiple of d, and when you reduce> that integer multiple of m mod n by subtracting a multiple of n> you will be subtracting a multiple of d from a multiple of d, so> you will get a multiple of d, so you won't get 1.I.e. suppose jm = 1 + kn, that is jm = 1 (mod n)Then d divides jm - kn = 1when d divides m & n-Bill Dubuque =I'm looking for information about an operator that I'venever seen before but that I'm sure must exist, alongwith a list of its properties, somewhere in the literature.If I have a sequence of numbers, de'ned by a function,I can use the summation operator to denote the sum ofthe 'rst n terms of the sequence. I can also use theproduct operator to denote the product of the 'rst nterms. What I would like to do is denote the exponentationof the 'rst n terms. For example, if I had a sequenceof numbers:f(x1), f(x2), f(x3), f(x4)...and (using O^' to indicate exponentiation) I wanted todenote:[[f(x1)^f(x2)]^f(x3)]^f(x4)...what operator, analogous to the classical summation andproduct operators, would I use?Kevin = Kevin Grant [CapitalEth][EDoubleDot][Micro] .b3 .b9[EDoubleDot].b9>> I'm looking for information about an operator that I've> never seen before but that I'm sure must exist, along> with a list of its properties, somewhere in the literature.>> If I have a sequence of numbers, de'ned by a function,> I can use the summation operator to denote the sum of> the 'rst n terms of the sequence. I can also use the> product operator to denote the product of the 'rst n> terms. What I would like to do is denote the exponentation> of the 'rst n terms. For example, if I had a sequence> of numbers:>> f(x1), f(x2), f(x3), f(x4)...>> and (using O^' to indicate exponentiation) I wanted to> denote:>> [[f(x1)^f(x2)]^f(x3)]^f(x4)...>> what operator, analogous to the classical summation and> product operators, would I use?http://www.4reference.net/encyclopedias/wikipedia/Hyper4. html> Kevin--Ioannis Galidakishttp://users.forthnet.gr/ath/jgal/------------------- -----------------------Eventually, _everything_ is understandable => I'm looking for information about an operator that I've> never seen before but that I'm sure must exist, along> with a list of its properties, somewhere in the literature. If I have a sequence of numbers, de'ned by a function,> I can use the summation operator to denote the sum of> the 'rst n terms of the sequence. I can also use the> product operator to denote the product of the 'rst n> terms. What I would like to do is denote the exponentation> of the 'rst n terms. For example, if I had a sequence> of numbers: f(x1), f(x2), f(x3), f(x4)... and (using O^' to indicate exponentiation) I wanted to> denote: [[f(x1)^f(x2)]^f(x3)]^f(x4)... what operator, analogous to the classical summation and> product operators, would I use?> This grouping is uninteresting, since it equals f(x1)^[product]More interesting is:f(x1)^[f(x2)^[f(x3)^...]]But even this is so seldom used that no sumbol has been proposed for it. => sure how this cashes out where the logic of identity is> concerned. One might construe the classical Ax[x=x <-> Ey(x=y)]> as characterizing by exclusion the relation between self-identity and> identity-with-something: no self-identical is an identical-with-nothing,> and no identical-with-something is a non-self-identical.Id really like to learn from you what it is like for something to benon-self-identical!Let me try to give an answer myself:- Two things that are identical with each other are not different fromeach other--and vice versa.- One thing that is identical with itself is not different fromitself, and vice versa- One thing that is not identical with itself is different fromitself.So what is it like for something to be different from itself?What does a is different from itself.mean in the 'rst place?In what respect could something be different from itself?Well, it could a) be numerically different from itselforb) be qualitatively different from itself.ad (a):I am convinced that the notion of Onumerical self-difference' does notmake any real sense!Is it logically possible for one thing to be not one thing, i.e. to betwo or many things (of the same kind), or no thing at all?! - I dontthink so!I venture to assert that anybody employing the notion of numericalself-difference doesnt really know what s/hes talking about!And if Onumerical self-difference' is unintelligible, then Onumericalnon-self-identity' is unintelligible as well!One thing must be one thing (of the same kind)!!!In other words, everything is necessarily numerically self-identical!ad (b):If something is qualitatively self-different, it possesses someproperties not possessed by it and, hence, must be a self-inconsistentobject:a /= a -> EP(Pa & ~Pa)Is it possible for there to be any real objects that areself-inconsistent?Well, dialetheists such as Graham Priest believe it is--but I dont!Summary:We have seen that the only intelligible meaning ofnon-self-identical is qualitativelynon-self-identical/qualitatively self-different, i.e. possessingsome properties not possessed by it!Both the notion of numerical non-self-identity and the related one ofqualitative non-self-identity are *inherently* contradictory!!!In my opinion that is the decisive reason why it is absolutelyimpossible for there to be anything non-self-identical!!!PHP.S.:To avoid a misunderstanding, in *pure* logic there may be consistentformalistic theories of non-self-identity, but there cannot be anyontological 'eld of application for those! =>> If something is qualitatively self-different, it possesses some> properties not possessed by it and, hence, must be a self-inconsistent> object:>Inyou will 'nd a description of a universe that is a proper part of itself.He calls it counterintuitive. I view it with about the same sense that yousuggest above.I believe it to be a failure to understand the relationships between mereology(part), set theory (element), and de'nite description (equals).It is not a matter of seeing whose is right and who is wrong. It is not amatter of this alternative foundation is better than that alternativefoundation. It is a matter of seeing how the identity puzzles are resolvingthemselves.Of course, everyone is so busy comparing deductive calculi and formal systems,they seem to have forgotten that these things arose from philosophicalconsiderations that were being debated prior to the introduction of suchcalculi.To the best of my knowledge, the only person out here quoting large passagesfrom philosophical texts is me.Perhaps Mr. Greene is right. Perhaps not.:-)mitch => If something is qualitatively self-different, it possesses some> properties not possessed by it and, hence, must be a self-inconsistent> object:> In > you will 'nd a description of a universe that is a proper part of itself. He calls it counterintuitive. I view it with about the same sense that you> suggest above. I believe it to be a failure to understand the relationships between mereology> (part), set theory (element), and de'nite description (equals). It is not a matter of seeing whose is right and who is wrong. It is not a> matter of this alternative foundation is better than that alternative> foundation. It is a matter of seeing how the identity puzzles are resolving> themselves. Of course, everyone is so busy comparing deductive calculi and formal systems,> they seem to have forgotten that these things arose from philosophical> considerations that were being debated prior to the introduction of such> calculi. Well, not everybody's doing that. Given that the philisophers who invented deductive calculi were Lawyers, science has bequeathed the whole issue to chemists and their mathema-lawyers. Everybody with regular computers is working on robots. To the best of my knowledge, the only person out here quoting large passages> from philosophical texts is me. Perhaps Mr. Greene is right. Perhaps not. :-) mitch => busy comparing deductive calculi > and formal systems,> they seem to have forgotten that these things arose from philosophical> considerations that were being debated prior to the introduction of such> calculi.Yes indeed. - And the philosophical debates continue even *after* thesuccessful construction of diverse calculi, each of which is provablyconsistent.No calculus can decide a philosophical problem.[Wittgenstein, L.. /The Big Typescript/ (Wiener Ausgabe, Bd. 11/Viennese Edition, vol. 11). Vienna: Springer. (p. 362)]Philosophers have been infatuated with the quanti'er. Understandablyso, since logicians showed the power and elegance of the predicatecalculus. And it is always tempting to want to put shiny new tools touse. If we translate some idiom of natural language into quanti'erform we feel we know how it works; we feel we have tamed it.[McGinn, C. (2000). /Logical Properties/. Oxford: Clarendon Press. (p.69)]PH =>Yes indeed. - And the philosophical debates continue even *after* the>successful construction of diverse calculi, each of which is provably>consistent.>>No calculus can decide a philosophical problem.>>[Wittgenstein, L.. /The Big Typescript/ (Wiener Ausgabe, Bd. 11/>Viennese Edition, vol. 11). Vienna: Springer. (p. 362)]No philosophy can decide a calculus problem. => although Benjamin Franklin is> necessarily self-identical, the inventor of bifocals is not> necessarily self-identical. ? - The inventor of bifocals existed, and whoever was the inventor ofbifocals was, of course, necessarily self-identical as long as heexisted!PH => In another post I suggested that John Correy's ideas aboutnon-re§exive> identity might have a rational formulation with respect tosomething> called counterpart theory.>> (I think categoreal would be the right term here--in my humble> opinion, the apparent self-contradictions associated with John's> intuitions arise from vagueness and ambiguity associated withstandard> presuppositions rather than irrational error on his part. For the> record, Langholm's investigation of determinability and> indeterminability in 'rst-order contexts includes incoherentformulas.> Exclusion negation is not informationally well-behaved.)>> The link,>> http://www.sussex.ac.uk//Users/muralir/kct_'nal.pdf> <>((x=x) & ~(x=x))>> is discussed as well as what is actually done in counterpart theoryto> exclude such an incoherent result.>> :-)>> mitch> http://www.sussex.ac.uk//Users/muralir/kct_'nal.pdf> <>((x=x) & ~(x=x))>> is discussed as well as what is actually done in counterpart theoryto> exclude such an incoherent result.>> :-)>> mitch>> The tie-in with contingent identity is as asserted by (1).>> (1) AxAy(x=y -> (N(x=x & y=y) <-> N(x=y)))>> That is, identical(x,y) are necessarily identical if, ond only if,> N(x=x) and N(y=y). Thus, granted that the Morning Star and the> Evening Star are each necessarily self-identical, if the Morning Star> and the Evening Star are identical, they are necessarily identical.> Hence the Morning Star and the Evening Star are necessarily> identical. The same is not true, however, for Benjamin Franklin> and the inventor of bifocals. For although Benjamin Franklin is> necessarily self-identical, the inventor of bifocals is not> necessarily self-identical. This is why Benjamin Franklin> and the inventor of bifocals, although identical are not> necessarily identical.>> --John>> I am not sure that my remarks are welcome here, I have had enough ofthe> remarks from (G. Frege)(II)> : stupid asshole, ing bitch, and all of that childish rhetoric, Icannot> reply to him at all.>> I assume that you guys are more mature than He.>> As to John's claim that: (John Correy = John Correy) is necessarilytrue, I> disagree.> It is not suf'cient to say, x=y <-> AF(Fx <-> Fy).> Rather, it is suf'cient to say, x=y <->. E!x & E!y &AF( Fx <-> Fy).>> After all, (ix: x=John Correy) is (John Correy).>> E!(John Correy) is just as doubtful as E!(The poster who claims that> ~Ax(x=x)).>> We cannot assume that E!(John Correy) any more than we can assume> E!(Vulcan)!>> (x=y) -> [](x=y) and E!x -> [](E!x), are consequences of Leibnitz's Law.>> There are no contingent existences nor contingent identities.> Exisence and Identity (and Membership) are analytic properties.>> Can we assume that: []Exists(George W. Bush)?>> I don't think so, do you?>> Surely, the existence of, George W. Bush, is contingent.>> There cannot be an assumption that all names of purported physicalentities> refer!>> Santa dosen't work, Vulcan doesn't work, Pegasus dosen't work, etc.>> For although Benjamin Franklin is necessarily self-identical, theinventor> of bifocals is not> necessarily self-identical.>> Benjamin Franklin = Benjamin Franklin, is not necessarily true.> (the inventor of bifocals)=(the inventor of bifocals), is also not> necessarily true, imo.>> Necessary identity and existence, applies to logical/mathematicalobjects,> not to emprical objects, imho.> Witt>> (1) states necessary and suf'cient conditions for the necessity of> (material) identity:>> (1) AxAy(x=y -> (N(x=x & y=y) <-> N(x=y)))Necessary self-identity is necessary existence.(1a) AxAy(x=y -> ((N(E!x) & N(E!y)) <-> N(x=y))If x and y are physical objectsI don't see necessity having sense wrt empirical things.If p is necessarily true then, it is logically true, ie. true in all timesfor which mind exists(within a speci'ed method of decision).Facts are not necessary, even though they are true. They happen to be truein our Opossible' world.[]E!(John Corry), means, John Correy exists is logically true.But, surely there are times at which John Correy, or any other proper nameof a physical object,does not refer to anything.Is E!(John Correy) true at (2,000,000 BC) or at (2,000,000 AD) ? Surelynot!Can we deduce that E!(John Correy)?For Ological objects' it is true, eg. E!1 is true at all times (for whichminds exist).But, I don't think that any physical object or physical relation, haslogical necessity, do you?>> If identicals x and y are necessarily self-identical, then--and> only then--is their identity a necessary one. Beyond this,> (1) states nothing more: from (1) it neither follows that> John Correy is necessarily self-identical nor that John> Correy is contingently self-identical--or indeed that John> Correy is self-identical at all. (1) does not say which of> the foregoing is the case.>> We can sit around and argue about whether you or I are necessarily> self-identical. However, although logicians do argue about such> matters--Who else would bother?--it is not as logicians that they> argue but as metaphysicians, or as pataphysicians, or as what have> you?>> So, when I claim that (e.g.) Benjamin Franklin is necessarily> self-identical while the inventor of bifocals is not, my main> warrant for this claim is that if Benjamin Franklin is necessarily> self-identical but the inventor of bifocals is not, then Benjamin> Franklin and the inventor of bifocals are not necessarily identical> (although they are identical). In other words, I take the necessary> self-identity of the former and the contingent self-identity of the> latter to constitute, together with (1), an *explanation* for the> contingent identity of Benjamin Franklin and the inventor of bifocals.>> To this you might object that these would be also be contingently> identical if both Benjamin Franklin and the inventor of bifocals were> contingently self-identical. To which I would respond that identities> involving what linguistically oriented analytical philosophers refer> to as rigid designators, are identities whose terms are necessarily> self-identical; whereas identities involving what such philosophers> refer to as non-rigid designators, are identities whose terms are> contingently self-identical. Therefore, granted that I take rigid and> non-rigid designation as the linguistic marks of necessary and> contingent self-identity--putting the cart back behind the horse,> rather than approaching the matter bass ackwards as it is> fashionable to do these days--and granted that I take> Benjamin Franklin and John Correy to be Origid' designators> and Othe inventor of bifocals' to be Onon-rigid', I conclude> that the contingent identity of Benjamin Franklin and the inventor> of bifocals has as its basis the contingent self-identity of the> inventor of bifocals, while Benjamin Franklin is necessarily> self-identical.Your distinction between named objects and described objects needsjusti'cation.Do you axiomatically grant necessary existence to named objects and possibleexistence to described objects?Why is Ben Franlklin more Onecessary' than the inventor of bi-focals?Note: Vulcan is the proper name given to a described planet which does notexist.Is there a Onecessary attribution' in the granting of proper names?>> As to whether physical or mathematical objects are contingently> self-identical or necessarily so, some sort of metaphysical argument> (rather than a logical one) warranting one or the other of these> conclusions would have to be made. I suspect that mathematical> properties are both essential in, and necessary to, mathematical> objects--but this is an intuition and nothing more.Our intuituitive Ometaphysics' entails that physical objects are indeedcontingent,contingent on presence, within a speci'ed time. There are no timelessphysical objects at all, are there?Given the existence of mind, all empirical things are time dependent, and,abstractthings are not.Witt>> John>> PS It won't surprise me if Paul Holbach or G. Frege bring in talk> about Oscope', which I think is only peripherally relevant to> discussions of necessary and contingent identity. =>> (1) states necessary and suf'cient conditions for the necessity of> (material) identity:>> (1) AxAy(x=y -> (N(x=x & y=y) <-> N(x=y))) Necessary self-identity is necessary existence. (1a) AxAy(x=y -> ((N(E!x) & N(E!y)) <-> N(x=y)) If x and y are physical objects I don't see necessity having sense wrt empirical things.> If p is necessarily true then, it is logically true, ie. true in all times> for which mind exists> (within a speci'ed method of decision).> Facts are not necessary, even though they are true. They happen to be true> in our Opossible' world. []E!(John Corry), means, John Correy exists is logically true.> But, surely there are times at which John Correy, or any other proper name> of a physical object,> does not refer to anything.> Is E!(John Correy) true at (2,000,000 BC) or at (2,000,000 AD) ? Surely> not!> Can we deduce that E!(John Correy)?There's a difference between N[Ex(John Correy = x)], which is false,and Ex(N[John Correy = x])--which is true. Not cashing assertionsout in primitive notation leads to a failure to discriminate suchreadings, in the 'rst of which N has operated on the sentence,Ex(John Correy = x), to make a sentence; and in the second ofwhich N has operated on an open formula, John Correy = x,to yield the open formula N(John Correy - x), which then gets'existentially' quanti'ed. For Ological objects' it is true, eg. E!1 is true at all times (for which> minds exist).> But, I don't think that any physical object or physical relation, has> logical necessity, do you?> If identicals x and y are necessarily self-identical, then--and> only then--is their identity a necessary one. Beyond this,> (1) states nothing more: from (1) it neither follows that> John Correy is necessarily self-identical nor that John> Correy is contingently self-identical--or indeed that John> Correy is self-identical at all. (1) does not say which of> the foregoing is the case.>> We can sit around and argue about whether you or I are necessarily> self-identical. However, although logicians do argue about such> matters--Who else would bother?--it is not as logicians that they> argue but as metaphysicians, or as pataphysicians, or as what have> you?>> So, when I claim that (e.g.) Benjamin Franklin is necessarily> self-identical while the inventor of bifocals is not, my main> warrant for this claim is that if Benjamin Franklin is necessarily> self-identical but the inventor of bifocals is not, then Benjamin> Franklin and the inventor of bifocals are not necessarily identical> (although they are identical). In other words, I take the necessary> self-identity of the former and the contingent self-identity of the> latter to constitute, together with (1), an *explanation* for the> contingent identity of Benjamin Franklin and the inventor of bifocals.>> To this you might object that these would be also be contingently> identical if both Benjamin Franklin and the inventor of bifocals were> contingently self-identical. To which I would respond that identities> involving what linguistically oriented analytical philosophers refer> to as rigid designators, are identities whose terms are necessarily> self-identical; whereas identities involving what such philosophers> refer to as non-rigid designators, are identities whose terms are> contingently self-identical. Therefore, granted that I take rigid and> non-rigid designation as the linguistic marks of necessary and> contingent self-identity--putting the cart back behind the horse,> rather than approaching the matter bass ackwards as it is> fashionable to do these days--and granted that I take> Benjamin Franklin and John Correy to be Origid' designators> and Othe inventor of bifocals' to be Onon-rigid', I conclude> that the contingent identity of Benjamin Franklin and the inventor> of bifocals has as its basis the contingent self-identity of the> inventor of bifocals, while Benjamin Franklin is necessarily> self-identical. Your distinction between named objects and described objects needs> justi'cation.> Do you axiomatically grant necessary existence to named objects and possible> existence to described objects? Why is Ben Franlklin more Onecessary' than the inventor of bi-focals?--One reason: replacing the dotted lines in ... need not have been ...by the inventor of bi-focals yields the true sentence, the inventorof bi-focals need not have been the inventor of bi-focals, whilereplacement with Benjamin Franklin yields the false sentence,Benjamin Franklin need not have been Benjamin Franklin. --Another reason: (1) is false but (2) is true.1) Benjamin Franklin didn't have to be Benjamin Franklin. 2) The inventor of bifocals didn't have to be the inventor of bifocals. Note: Vulcan is the proper name given to a described planet which does not> exist. Is there a Onecessary attribution' in the granting of proper names?> As to whether physical or mathematical objects are contingently> self-identical or necessarily so, some sort of metaphysical argument> (rather than a logical one) warranting one or the other of these> conclusions would have to be made. I suspect that mathematical> properties are both essential in, and necessary to, mathematical> objects--but this is an intuition and nothing more. Our intuituitive Ometaphysics' entails that physical objects are indeed> contingent,> contingent on presence, within a speci'ed time. There are no timeless> physical objects at all, are there?> Given the existence of mind, all empirical things are time dependent, and,> abstract> things are not. Witt--John => V1qrb.188420$7B1.55593@news04.bloor.is.net.cable.rogers.com>.. .> Why is Ben Franlklin more Onecessary' than the inventor of bi-focals?> --One reason: replacing the dotted lines in > ... need not have been ...> by the inventor of bi-focals yields the true sentence, the inventor> of bi-focals need not have been the inventor of bi-focals, while> replacement with Benjamin Franklin yields the false sentence,> Benjamin Franklin need not have been Benjamin Franklin. --Another reason: (1) is false but (2) is true. 1) Benjamin Franklin didn't have to be Benjamin Franklin. 2) The inventor of bifocals didn't have to be the inventor of bifocals. Youre mistaken!It is true that Benjamin Franklin didnt have to be the inventor ofbifocals, and it is equally true that the inventor of bifocals didnthave to be Benjamin Franklin.It is also true that the person actually referred to by the inventorof bifocals might have not invented the bifocals; and if that werethe case, we certainly wouldnt nowadays refer to *that* particularperson by the inventor of bifocals. But all this does in no wayimply that whoever is the one we refer to by the inventor ofbifocals is not necessarily self-identical! Even if new historicalresearch showed surprisingly that the particular person we actuallyrefer to by the inventor of bifocals didnt actually invent thebifocals, that person we would then erroneously refer to by theinventor of bifocals would nevertheless remain necessarilyself-identical!The inventor of bifocals would be necessarily self-identical, even ifthat particular person had not invented the bifocals. If that were thecase, then the inventor of bifocals would be a pseudo-descriptionfunctioning just like any arbitrary proper noun!We can successfully identify particular objects even by means ofpseudo-descriptions.ixFx = ixFxis necessarily true, whileFixFx is contingently true.Your basic mistake is to suppose that the contingency of OFixFx'implies the contingency of OixFx = ixFx'--but this is simply not thecase!The way we linguistically refer to things doesnt affect their beingnecessary self-identical at all!For example, we could decide to henceforth refer to Bill Clinton bythe inventor of bifocals, knowing that not Clinton but Franklinactually invented the bifocals (the latter might then be re-baptizedthe real inventor of bifocals ;-)). But that wouldnt turn[](the inventor of bifocals = the inventor of bifocals)into a false statement!Your notion of Ocontingent identity' is based on a misconstruction!PH => V1qrb.188420$7B1.55593@news04.bloor.is.net.cable.rogers.com>.. .> Why is Ben Franlklin more Onecessary' than the inventor of bi-focals?> --One reason: replacing the dotted lines in> ... need not have been ...> by the inventor of bi-focals yields the true sentence, the inventor> of bi-focals need not have been the inventor of bi-focals, while> replacement with Benjamin Franklin yields the false sentence,> Benjamin Franklin need not have been Benjamin Franklin.>> --Another reason: (1) is false but (2) is true.>> 1) Benjamin Franklin didn't have to be Benjamin Franklin.>> 2) The inventor of bifocals didn't have to be the inventor of bifocals.> Youre mistaken!>> It is true that Benjamin Franklin didnt have to be the inventor of> bifocals, and it is equally true that the inventor of bifocals didnt> have to be Benjamin Franklin.> It is also true that the person actually referred to by the inventor> of bifocals might have not invented the bifocals; and if that were> the case, we certainly wouldnt nowadays refer to *that* particular> person by the inventor of bifocals. But all this does in no way> imply that whoever is the one we refer to by the inventor of> bifocals is not necessarily self-identical! Even if new historical> research showed surprisingly that the particular person we actually> refer to by the inventor of bifocals didnt actually invent the> bifocals, that person we would then erroneously refer to by the> inventor of bifocals would nevertheless remain necessarily> self-identical!>> The inventor of bifocals would be necessarily self-identical, even if> that particular person had not invented the bifocals. If that were the> case, then the inventor of bifocals would be a pseudo-description> functioning just like any arbitrary proper noun!> We can successfully identify particular objects even by means of> pseudo-descriptions.>> ixFx = ixFx>> is necessarily true, while>> FixFx is contingently true.Not so, for Russell's description theory.1. G(ix:Fx) <-> Ey(Ax(x=y <-> Fx) & Gy), see PM *14.12. E!(ix:Fx) <-> Ey(Ax(x=y <-> Fx), see *14.23. E!(ix:Fx) <-> F(ix:Fx)4. E!(ix:Fx) <-> (ix:Fx)=(ix:Fx)5. E!(ix:Fx) <-> EG(G(ix:Fx))6. F(ix:Fx) <-> (ix:Fx)=(ix:Fx)7. [](F(ix:Fx)) <-> []((ix:Fx)=(ix:Fx))By: 6, |-p -> |-[]p, and, [](p <-> q) -> ([]p <-> []q).8. []E!(ix:Fx) <-> []((ix:Fx)=(ix:Fx)).Witt> Your basic mistake is to suppose that the contingency of OFixFx'> implies the contingency of OixFx = ixFx'--but this is simply not the> case!>> The way we linguistically refer to things doesnt affect their being> necessary self-identical at all!>> For example, we could decide to henceforth refer to Bill Clinton by> the inventor of bifocals, knowing that not Clinton but Franklin> actually invented the bifocals (the latter might then be re-baptized> the real inventor of bifocals ;-)). But that wouldnt turn>> [](the inventor of bifocals = the inventor of bifocals)>> into a false statement!>> Your notion of Ocontingent identity' is based on a misconstruction!>> PH => IIVrb.16233$Rah1.1560@twister01.bloor.is.net.cable.rogers.com> ...> ixFx = ixFx>> is necessarily true, while>> FixFx is contingently true. > Not so, for Russell's description theory. 1. G(ix:Fx) <-> Ey(Ax(x=y <-> Fx) & Gy), see PM *14.1 2. E!(ix:Fx) <-> Ey(Ax(x=y <-> Fx), see *14.2 3. E!(ix:Fx) <-> F(ix:Fx)> 4. E!(ix:Fx) <-> (ix:Fx)=(ix:Fx)> 5. E!(ix:Fx) <-> EG(G(ix:Fx))> 6. F(ix:Fx) <-> (ix:Fx)=(ix:Fx) 7. [](F(ix:Fx)) <-> []((ix:Fx)=(ix:Fx))> By: 6, |-p -> |-[]p, and, [](p <-> q) -> ([]p <-> []q). 8. []E!(ix:Fx) <-> []((ix:Fx)=(ix:Fx)).Youre not wrong insofar as there really seems to be a problem for theNFL-logician, for whom(1) ixFx = ixFx -> E!ixFxis impeccable.If the normal rules of modal logic (particularly the rule ofnecessitation and the rule of box distribution), are applied to (1),we indeed get the following result:[](ixFx = ixFx) -> []E!ixFxBut once again, were being confronted with the notorious ambiguity ofmodal formulas.Read de dicto we have:If OixFx = ixFx' is necessarily true, then OE!ixFx' is necessarilytrue.The point is that in negative free logic ixFx = ixFx is not anecessary truth, since it is possibly false (in case ~E!ixFx). Thereis a possible world in which ixFx = ixFx is false because ixFx doesnot exist in that world; and if there is a possible world in whichixFx doesnt exist, E!ixFx cannot be a necessary truth either, sincenecessary truth is de'ned as truth in all worlds!Even though (ixFx = ixFx) -> E!ixFx is a necessary NFL-truth, bothixFx = ixFx and E!ixFx are no necessary NFL-truths!But, luckily, that circumstance does not render the followingimplication untrue:[](ixFx = ixFx -> E!ixFx) -> ([](ixFx = ixFx) -> []E!ixFx)The antecedent is true but neither the antecedent nor the consequentof the consequent are true in NFL!So we have1 -> (0 -> 0) 1 -> 11 !By the way, the rule of necessitation can also be unproblematicallyapplied to the following NFL-theorem:Ax(x = x -> E!x)[]Ax(x = x -> E!x)[](Ax(x = x) -> AxE!x)[]Ax(x = x) -> []AxE!xSince in NFL both Ax(x = x) and AxE!x are axioms, everythings 'nehere!What if we interpreted (1) *de re*?In NFLE!x <-> Ey(y = x)holds (by de'nition), and so we can write(1*) ixFx = ixFx -> Ey(y = ixFx)and [](ixFx = ixFx) -> Ey[](y = ixFx)If ixFx is necessarily self-identical, then there is something suchthat it is necessarily identical with ixFx.(It doesnt mean ... there necessarily is something such that...!!!)This de re interpretation is impeccable, for now both the antecedentand the consequent are true!PH => V1qrb.188420$7B1.55593@news04.bloor.is.net.cable.rogers.com>.. .> Necessary self-identity is necessary existence.I dont think so!While Ax[]([](x = x) -> E!x)is true,Ax([](x = x) ->[]E!x)is not.Modality *de re* is modality thought of as applying to a thing(Ores'), more precisely, as a way a thing possesses a property. [...]Modality *de dicto* is the modality applied to a statement (Odictum').It refers to the manner or mode of a statements being true.[Konyndyk, K. (1986). /Introductory Modal Logic/. Notre Dame, IN:University of Notre Dame Press. (p. 78f)]Now we are ready to try to give a properly de re reading ofstatements like OSocrates is essentially rational'. An individual issaid to have a given property essentially if and only if it is notpossible that the individual exist and lack the property.Alternatively, an individual must have the property in every world inwhich it exists. This account [...] has some implications of its ownthat should be observed. The 'rst implication is that anything thatexists has existence essentially.[Konyndyk, K. (1986). /Introductory Modal Logic/. Notre Dame, IN:University of Notre Dame Press. (p. 89)]I can sum up what I just argued by saying that in a modal sentencethe copula is not modally neutral. And isnt this exactly the way weread such sentences? Dont they precisely say that a property is hadin the mode of necessity or in the mode of contingency? We start byremarking that Socrates is a man and then, when our thoughts turnmodal, we want to know whether this property inheres in Socrates inthe necessary way or the contingent way: *how* is he a man? What weare interested in is *mode of instantiation*. Modals are modes. To saythat modal words modify the copula is the linguistic counterpart ofthe ontological doctrine that modality is a matter of the strength ofthe instantiation relation: does the object in question instantiatethe predicated property only accidentally or is this a matter o§ogical or metaphysical necessity ($). Thus, according to the copulamodi'er theory, we do not work with an ontology of modal properties;rather, we take the stock of non-modal properties and think of them aspossessed in different modes. If you like, the instantiation relationis the only thing that gives rise to modal properties--the propertiesof being instantiated necessarily or contingently.($: What of Oa is possibly F', where this can be true even though theobject doesnt actually have the property? In this case, obviously, wecannot be saying in what mode the object *has* the property, since itdoesnt have it. Instead, we are saying that the object possiblyinstantiates the property, where again the modal expression modi'esthe copula, as in OSocrates possibly-is a man'.)[McGinn, C. (2000). /Logical Properties/. Oxford: Clarendon Press. (p.77)]In that sense the statementsEverything is necessarily self-identical.andEverything is necessarily existent.mean thatEverything instantiates the property of self-identity in thenecessary way.andEverything (i.e. every existing thing!) instantiates the property ofexistence in the necessary way.The latter statement is, of course, not equivalent toEverything (i.e. every existing thing!) instantiates the property ofnecessary existence in the necessary way. !PH => V1qrb.188420$7B1.55593@news04.bloor.is.net.cable.rogers.com>.. .> (Necessary self-identity is necessary existence.)Put that way, one can state the following without there being anyinconsistency whatsoever:Ax(E!x -> []E!x)Correction:It now seems to me thatAx[](E!x -> E!x)is the adequate formulation ofEverything is essentially such that if it exists, it exists.Nothing can exist without existing.PH => V1qrb.188420$7B1.55593@news04.bloor.is.net.cable.rogers.com>.. .> Necessary self-identity is necessary existence.Depends on what a theory of modal logic is intended to validate!(Frankly, Im not a fan of the Barcan formulas ...)In other words, the matter of scope is decisive.I think the only acceptable EG of O[](a = a)' is as follows:[](a = a) -> Ex[](x = a)If a is necessarily identical with itself, then there is somethingsuch that a is necessarily identical with it.Here, the box is interpreted *de re*, for the necessity lies in therelation of identity and not in the possession of existence!> []E!(John Corry), means, John Correy exists is logically true.This is the de dicto reading, but one could as well read it de re,i.e. asJohn Correy necessarily exists .In classical logic existential statements of the type OEx(x = a)' aretheorems which are considered necessary truths *by mere stipulation*,for--by de'nition--non-referring singular terms are not allowed init.But since there are in actual fact many non-referring singular termsin ordinary language, free logic is preferable to classical logic. Inthe former, no existential statement of the type OE!a' [<-> Ex(x = a)]is a theorem.> But, I don't think that any physical object or physical relation, has> logical necessity, do you?Ex[](x = John Correy)There is something such that it is necessarily identical with JohnCorrey.It does not follow thatThere necessarily exists something such that it is identical withJohn Correy.Once again, one must systematically differentiate between de dictonecessities (necessary truths) and de re necessities (essentialproperties)!We are going to take *de re* modality to express the essentialpossession of a property by an individual. We use the O[]' torepresent *de re* as well as *de dicto* modality. In our symbolism, wewill continue to regard an occurrence of a modality sign asrepresenting modality *de dicto* if and only if that formula and onlythat formula within the scope of modality contains no free occurrencesof any individual variables. The easiest way to apply this test is asfollows:Delete all parts of the whole formula except for what appears withinthe scope of the modal sign under consideration. If what remainscontains no free occurrences of any individual variable, the modalityis *de dicto*. Correspondingly, a modality is considered *de re* ifand only if the formula within the scope of the modality does containat least one free occurrence of an individual variable. Hence, in thefollowing example, the 'rst (outermost) occurrence of O[]' ismodality *de dicto* and the second occurrence of O[]' is modality *dere*: [](x)[](Cx -> Hx)In giving rules for quanti'ed modal logic, we frequently will beforced to take stands on complex and hotly disputed metaphysicalissues involved in understanding essence and existence, and *de re*and *de dicto* modality.[...]7. An individual has a property essentially just in case thatindividual has that property in every world in which that individualexists.8. The *de re* understanding of Onecessarily' or O[]' is as'essentially'.[Konyndyk, K. (1986). /Introductory Modal Logic/. Notre Dame, IN:University of Notre Dame Press. (pp. 83 + 91)]Put that way, one can state the following without there being anyinconsistency whatsoever:Ax(E!x -> []E!x)For every x, if x exists, then x is essentially existent.That is, as long as x exists it is impossible for it to benon-existent.It may appear illogical at 'rst sight, but theres nothing wrong insaying that existence is not an accidental but an essential propertyof every contingent thing--of every existing contingent thing!That existence is an essential property means that it is possible fornothing to lose the property of existence without ceasing to exist!There is a crucial difference between Every existent necessarily_is existent.andEvery existent is necessarily_existent.,forEverything necessarily_has the property of existence.certainly doesnt mean the same asEverything (necessarily) has the property of necessary_existence.Its a real blemish of modal logic that its formulas are veryambiguous.For example, in the case of self-identity it might be useful if wedwriteAx(x []= x)instead ofAx[](x = x) (both de re formulations).But in my opinion Konyndyks interpretation (see above) is agreeablealready.PH =According to a researcher at Sandia National Labs, the 3-D Ising Model iscomputationally intractible. Supposedly, the critical temperature,magnetic susceptibility, etc. cannot be evaluated analytically like in the2-D Ising Model.http://www.sandia.gov/media/NewsRel/NR2000/ising.htmIs this considered to be a de'nitive proof that the long-studied 3-DIsing Model can't be solved analytically, or are there differentinterpretations of these results? => According to a researcher at Sandia National Labs, the 3-D Ising Model is> computationally intractible. Supposedly, the critical temperature,> magnetic susceptibility, etc. cannot be evaluated analytically like in the> 2-D Ising Model. http://www.sandia.gov/media/NewsRel/NR2000/ising.htm Is this considered to be a de'nitive proof that the long-studied 3-D> Ising Model can't be solved analytically, or are there different> interpretations of these results?Recently, I heard a talk of an experimental physicist who thinks thatsimulation of such models will be the 'rst useful application of quantumcomputing in 5 to 10 years.-- =>According to a researcher at Sandia National Labs, the 3-D Ising Model is>computationally intractible. Supposedly, the critical temperature,>magnetic susceptibility, etc. cannot be evaluated analytically like in the>2-D Ising Model.>http://www.sandia.gov/media/NewsRel/NR2000/ising.htm>Is this considered to be a de'nitive proof that the long-studied 3-D>Ising Model can't be solved analytically, or are there different>interpretations of these results?I took a brief look at Istrail's 'rst paper, Statistical Mechanics, Three-Dimensionality and NP-completeness I. Universality of Intractabilityfor the Partition Function of the Ising Model Across Non-Planar Latticeswhen it came out about 3 years ago, and it seems to me that there's a bit less here than what the press release claimed.Onsager's solution of the 2D Ising model consists basically of a closed-form expression for the free energy (in the in'nite-volumelimit, as a function of the interaction strength J). Now one way of obtaining Onsager's result, using Pfaf'ans, is related to a counting problem. As far as I can tell, the connection to NP-completeness is that on a planar lattice the Pfaf'an provides a polynomial-time method for solving a certain class of counting problem. Therefore (unless P=NP) this class of problems can't be NP-hard. It seems that Istrail shows that on anon-planar lattice the analogous class of problems is NP-hard. But that is a far cry from saying that there is no closed-formexpression for the free energy. At most it shows that one particularmethod of obtaining such an expression won't work. Robert Israel israel@math.ubc.caDepartment of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 =>According to a researcher at Sandia National Labs, the 3-D Ising Model is>computationally intractible. Supposedly, the critical temperature,>magnetic susceptibility, etc. cannot be evaluated analytically like inthe>2-D Ising Model.>>http://www.sandia.gov/media/NewsRel/NR2000/ising.htm>> Is this considered to be a de'nitive proof that the long-studied 3-D>Ising Model can't be solved analytically, or are there different>interpretations of these results?>> I took a brief look at Istrail's 'rst paper, Statistical Mechanics,> Three-Dimensionality and NP-completeness I. Universality of Intractability> for the Partition Function of the Ising Model Across Non-Planar Lattices> when it came out about 3 years ago, and it seems to me that there's a> bit less here than what the press release claimed.>> Onsager's solution of the 2D Ising model consists basically of> a closed-form expression for the free energy (in the in'nite-volume> limit, as a function of the interaction strength J). Now one way of> obtaining Onsager's result, using Pfaf'ans, is related to a counting> problem. As far as I can tell, the connection to NP-completeness is that> on a planar lattice the Pfaf'an provides a polynomial-time method for> solving a certain class of counting problem. Therefore (unless P=NP) this> class of problems can't be NP-hard. It seems that Istrail shows that on a> non-planar lattice the analogous class of problems is NP-hard.> But that is a far cry from saying that there is no closed-form> expression for the free energy. At most it shows that one particular> method of obtaining such an expression won't work.>> => Some languages have several sets of words for numbers, with different> sets used for counting different things. Analogous too close to the> 're pragmatic redundancy is seen a typical C program (even more> in C++), where the very same thing is coded 5 different ways, each> named in accordance with its application (as good naming convention> dictates), thus totally obscuring the fact that it was the same thing.Well, I agree that redundancy is not just a phenomenon in mathematics.However, I see it as a result of arbitrary decisions instead of more reasonable natural ones.Well, mathematics is not a Naturwissenschaft. It rather depends on application on nature whether or not mathematics is actually natural.If causal functions of time do not need a second limit of integration, then the second limit might be redundant in this particular case.What might correspond to the 'x limit of integration?Derivative also tacitly relates to zero.Having removed the perhaps redundant second limit, I wonder that integration and derivative are more of the same kind.So far, derivative of a function of time is considered to loose information. =>>I repeatedly found the word causal in titles of books on mathematical>>subjects. > I didn't.For instance:Academic Press 1977 includes many referencesA. Aulin: Foundation of mathematical system dynamics: The fundamental theory of causal recursion and its application to social science and economics, Pergamon Press 1989 = >>I repeatedly found the word causal in titles of books on mathematical>subjects.>> I didn't. > For instance: Academic Press 1977 includes many references A. Aulin: Foundation of mathematical system dynamics: The fundamental> theory of causal recursion and its application to social science and> economics, Pergamon Press 1989Aha! repeatedly equals twice!Incidentally I found neither of these books on MathSciNethttp://e-math.ams.org/mathscinet-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) =>Aha! repeatedly equals twice!Isn't it standard mathematical notation to imply countably in'nitesequences as 1,2,...? That means once you have two you can extrapolateto in'nity. =>Aha! repeatedly equals twice! Isn't it standard mathematical notation to imply countably in'nite> sequences as 1,2,...?Is it?One hears tales of remote tribes whose counting is limitedto one and many ...> That means once you have two you can extrapolate> to in'nity.Ah yes! As there are two twin primes, there must be in'nitelymany :-)-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) =I apologize for being somewhat busy and lazy. If you are really interested in the topic, you will already 'nd further titles with the word causal within a comprehensive list of references provided by the 'rst reference I pointed you to. As I alluded, this hardbound book is a little bit too mathematical to me. I mainly looked into the introduction and was rather disappointed albeit I got the impression that the author has been knowing a lot of previous and related work.Eckard Blumschein >Aha! repeatedly equals twice!>>Isn't it standard mathematical notation to imply countably in'nite>>sequences as 1,2,...? > Is it? One hears tales of remote tribes whose counting is limited> to one and many ... >>That means once you have two you can extrapolate>>to in'nity. > Ah yes! As there are two twin primes, there must be in'nitely> many :-)> =I do not know much about prepositional resolution and have aquestion, which sounds trivial, yet I am still not sure what theanswer is.We have that:1)The empty clause {} is unsatis'able.2)The empty set of clauses is satis'able.A set of clauses that contain just the empty clause - is itsatis'able or unsatis'able? = I do not know much about prepositional resolution and have a> question, which sounds trivial, yet I am still not sure what the> answer is. We have that:> 1)The empty clause {} is unsatis'able.> 2)The empty set of clauses is satis'able. A set of clauses that contain just the empty clause - is it> satis'able or unsatis'able?Assuming the obvious de'nition for satis'ability of sets of clauses - i.e. that a set of clauses is satis'able if and only if all its members are - the answer is no, since the set containing just the empty clause does not have all its members satis'able.-- Aatu Koskensilta (aatu.koskensilta@xortec.')Wovon man nicht sprechen kann, daruber muss man schweigen - Ludwig Wittgenstein, Tractatus Logico-Philosophicus =integral from 0 to in'nity of sin(x) / x is pi/2.What sould I do to calculate out this result? it out? => integral from 0 to in'nity of sin(x) / x is pi/2.> What sould I do to calculate out this result?There is a complex variable approach to this problem. Considerthe function f(z) = (exp(i z) - 1)/z for z different from 0 andf(0) = i; consider also, for each R > 0, the following path:it goes from -R to R in a straight linea and then from R to -Ragain through the half-circle with center in 0 that passesthrough iR. Then, since f is analytic, the integral of f alongthis path is 0. You can use this to prove that the limit ofthe integral of f between -oo and +oo is equal to i.pi. Sincesin(x)/x = Im(f(x)), it follows that the integral of sin(x)/xbetween -oo and +oo is equal to pi.Jose Carlos Santos out? = integral from 0 to in'nity of sin(x) / x is pi/2.> What sould I do to calculate out this result?Use Fourier transform, very easy. Quick outline, all sorts of constantsare not considered here:If f(t) is de'ned as: f(t) = 0, |t| > 1 f(t) = 1, |t| <= 1then its Fourier transform F(w) is of the form sin(w)/w (see lookuptables...): +infty 1 F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt -infty -1Or easy to compute yourself also...The transform back is de'ned by: +infty f(t) = 1/(2pi) INT F(w) exp(jwt) dw -inftyIn your case: +infty f(0) = 1/(2pi) INT F(w) dw -infty Because F(w) is even: +infty pi*f(0) = pi = INT F(w) dw 0 Something like that... You've to work it out to get the constants right. Jeroen =>> integral from 0 to in'nity of sin(x) / x is pi/2.>> What sould I do to calculate out this result? > Use Fourier transform, very easy. Quick outline, all sorts of constants> are not considered here: If f(t) is de'ned as: f(t) = 0, |t| > 1> f(t) = 1, |t| <= 1 then its Fourier transform F(w) is of the form sin(w)/w (see lookup> tables...): +infty 1> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt> -infty -1j?> The transform back is de'ned by: +infty> f(t) = 1/(2pi) INT F(w) exp(jwt) dw> -inftyDe'ned by, or is? Of course, in our case F is not an L_1 functionand so one has to be careful about these improper limits.Incidentally, in this case, is your formula true for t = 1?I seem to remember from my undergraduate daysthat the proof we saw of the Fourier inversion theoremwas dependent on the identity pi/2 = integral_0^in'nity sin(x)/ x dx.Could you outline a proof of the Fourier inversion theorem,valid pointwise (under suitable hypotheses) not using this identity?-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) =>integral from 0 to in'nity of sin(x) / x is pi/2.>What sould I do to calculate out this result?>> Use Fourier transform, very easy. Quick outline, all sorts of constants>> are not considered here:>> If f(t) is de'ned as: f(t) = 0, |t| > 1>> f(t) = 1, |t| <= 1>> then its Fourier transform F(w) is of the form sin(w)/w (see lookup>> tables...):>> +infty 1>> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt>> -infty -1>>j?> The transform back is de'ned by:>> +infty>> f(t) = 1/(2pi) INT F(w) exp(jwt) dw>> -infty>>De'ned by, or is? Of course, in our case F is not an L_1 function>and so one has to be careful about these improper limits.>Incidentally, in this case, is your formula true for t = 1?>>I seem to remember from my undergraduate days>that the proof we saw of the Fourier inversion theorem>was dependent on the identity pi/2 = integral_0^in'nity sin(x)/ x dx.>>Could you outline a proof of the Fourier inversion theorem,>valid pointwise (under suitable hypotheses) not using this identity?Not going to get the constants straight - using the Extended Littlewood Convention, to the effect that pi = 2pi = -1 = etc = 1.(Of course this makes 'nding that integral easy...) Using * onlyfor convolution; using ^ both for the Fourier Transform and the(formal) inverse Fourier Transform:Roughly speaking you only need to calculate _any_ suitableFourier Transform pair (ie 'nd f^ and f^^ for any suitablef). The approaches I know all involve knowing at least onenot-quite-elementary integral, but it doesn't have to besin(x)/x.My favorite uses G(x) = exp(-xx/2), because then there's onlyone Fourier Transform to calculate: You note that G'(x) + x G(x) = 0,you verify that under suitable hypotheses (xf(x))^ and(f')^ are what they should be, and it follows that G^ satis'es the same differential equation. So G^ is amultiple of G, and calculating the integral of G showsthat G^ = G.Now Fubini shows that int f^ g = int f g^ for f, g in L^1.It follows that (*) (f^ g)^ = f * g^ (f, g in L^1).Let G_d(x) = d G(dx) and G__d(x) = G(x/d). If you apply(*) with g = G__d and let d -> in'nity it follows thatf = f^^ (ae) if f and f^ are both in L^1. You alsoget the Plancherel theorem from (*) (prove 'rst withf in L^1 intersect L^2, using (*) with g = G__d andf replaced by the f*h, where h(x) = f(-x), or maybeit's conjugate(f(-x)), whatever so that h^ = conjugate(f^).)So now the FT is an isometry on L^2 which agrees with theoriginal FT on L^2 intersect L^1.Ok. Now let s(x) = sin(x)/x, chi = the characteristicfunction of [-1,1]. You calculate that chi^ = s, and itfollows that s^ = chi. Of course we're not done, becausethat s^ is the L^2 FT, not the limit of the integralfrom -A to A.But an elementary argument shows that the principal-valueintegral of s is equal to the limit of int s G__d asd -> in'nity (the same argument that shows the tailof int s -> 0 shows that the tail of int s G__d -> 0,_uniformly_ in d...) So we need only evaluate thelimit of int s G__d.But (*) (with f = chi, an L^1 function) shows thatint(s G__d) = int(chi G_d), and this tends to chi(0)as d -> in'nity because chi is continuous at 0.(Yes, if we just want int s then the thing you postedis much simpler - the trickiness there is the sameas in the elementary argument two paragraphs above.But you asked, and it does seem worth noting thatthe integral of s is not essential in proving thebasic facts about the Fourier Transform. Me, I wasbrought up wrong, with an emphasis on convergencein norm instead of pointwise convergence - I'm notgoing to tell you how old I was the day I got thatstrange look from a colleague after revealing Ididn't even realize that the integral of s hadanything to do with the FT...)>-- >Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.html>Needless to say, I had the last laugh.> Alan Partridge, _Bouncing Back_ (14 times)David C. Ullrich =>Could you outline a proof of the Fourier inversion theorem,>>valid pointwise (under suitable hypotheses) not using this identity? Not going to get the constants straight - using the Extended> Littlewood Convention, to the effect that pi = 2pi = -1 = etc = 1.> (Of course this makes 'nding that integral easy...) Using * only> for convolution; using ^ both for the Fourier Transform and the> (formal) inverse Fourier Transform: Roughly speaking you only need to calculate _any_ suitable> Fourier Transform pair (ie 'nd f^ and f^^ for any suitable> f). The approaches I know all involve knowing at least one> not-quite-elementary integral, but it doesn't have to be> sin(x)/x. My favorite uses G(x) = exp(-xx/2), because then there's only> one Fourier Transform to calculate: You note that G'(x) + x G(x) = 0, you verify that under suitable hypotheses (xf(x))^ and> (f')^ are what they should be, and it follows that G^> satis'es the same differential equation. So G^ is a> multiple of G, and calculating the integral of G shows> that G^ = G. Now Fubini shows that int f^ g = int f g^ for f, g in L^1.> It follows that (*) (f^ g)^ = f * g^ (f, g in L^1). Let G_d(x) = d G(dx) and G__d(x) = G(x/d). If you apply> (*) with g = G__d and let d -> in'nity it follows that> f = f^^ (ae) if f and f^ are both in L^1. You also> get the Plancherel theorem from (*) (prove 'rst with> f in L^1 intersect L^2, using (*) with g = G__d and> f replaced by the f*h, where h(x) = f(-x), or maybe> it's conjugate(f(-x)), whatever so that h^ = conjugate(f^).)> So now the FT is an isometry on L^2 which agrees with the> original FT on L^2 intersect L^1. Ok. Now let s(x) = sin(x)/x, chi = the characteristic> function of [-1,1]. You calculate that chi^ = s, and it> follows that s^ = chi. Of course we're not done, because> that s^ is the L^2 FT, not the limit of the integral> from -A to A. But an elementary argument shows that the principal-value> integral of s is equal to the limit of int s G__d as> d -> in'nity (the same argument that shows the tail> of int s -> 0 shows that the tail of int s G__d -> 0,> _uniformly_ in d...) So we need only evaluate the> limit of int s G__d. But (*) (with f = chi, an L^1 function) shows that> int(s G__d) = int(chi G_d), and this tends to chi(0)> as d -> in'nity because chi is continuous at 0. (Yes, if we just want int s then the thing you posted> is much simpler - the trickiness there is the same> as in the elementary argument two paragraphs above.> But you asked, and it does seem worth noting that> the integral of s is not essential in proving the> basic facts about the Fourier Transform. Me, I was> brought up wrong, with an emphasis on convergence> in norm instead of pointwise convergence - I'm not> going to tell you how old I was the day I got that> strange look from a colleague after revealing I> didn't even realize that the integral of s had> anything to do with the FT...)Well done David! I hope Mr Boschma now realizesall the little details he's sweeping under the carpet ... :-)-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) =>>Could you outline a proof of the Fourier inversion theorem,>>valid pointwise (under suitable hypotheses) not using this identity?>> Not going to get the constants straight - using the Extended> Littlewood Convention, to the effect that pi = 2pi = -1 = etc = 1.> (Of course this makes 'nding that integral easy...) Using * only> for convolution; using ^ both for the Fourier Transform and the> (formal) inverse Fourier Transform:>> Roughly speaking you only need to calculate _any_ suitable> Fourier Transform pair (ie 'nd f^ and f^^ for any suitable> f). The approaches I know all involve knowing at least one> not-quite-elementary integral, but it doesn't have to be> sin(x)/x.>> My favorite uses G(x) = exp(-xx/2), because then there's only> one Fourier Transform to calculate: You note that>> G'(x) + x G(x) = 0,>> you verify that under suitable hypotheses (xf(x))^ and> (f')^ are what they should be, and it follows that G^> satis'es the same differential equation. So G^ is a> multiple of G, and calculating the integral of G shows> that G^ = G.>> Now Fubini shows that int f^ g = int f g^ for f, g in L^1.> It follows that>> (*) (f^ g)^ = f * g^ (f, g in L^1).>> Let G_d(x) = d G(dx) and G__d(x) = G(x/d). If you apply> (*) with g = G__d and let d -> in'nity it follows that> f = f^^ (ae) if f and f^ are both in L^1. You also> get the Plancherel theorem from (*) (prove 'rst with> f in L^1 intersect L^2, using (*) with g = G__d and> f replaced by the f*h, where h(x) = f(-x), or maybe> it's conjugate(f(-x)), whatever so that h^ = conjugate(f^).)> So now the FT is an isometry on L^2 which agrees with the> original FT on L^2 intersect L^1.>> Ok. Now let s(x) = sin(x)/x, chi = the characteristic> function of [-1,1]. You calculate that chi^ = s, and it> follows that s^ = chi. Of course we're not done, because> that s^ is the L^2 FT, not the limit of the integral> from -A to A.>> But an elementary argument shows that the principal-value> integral of s is equal to the limit of int s G__d as> d -> in'nity (the same argument that shows the tail> of int s -> 0 shows that the tail of int s G__d -> 0,> _uniformly_ in d...) So we need only evaluate the> limit of int s G__d.>> But (*) (with f = chi, an L^1 function) shows that> int(s G__d) = int(chi G_d), and this tends to chi(0)> as d -> in'nity because chi is continuous at 0.>> (Yes, if we just want int s then the thing you posted> is much simpler - the trickiness there is the same> as in the elementary argument two paragraphs above.> But you asked, and it does seem worth noting that> the integral of s is not essential in proving the> basic facts about the Fourier Transform. Me, I was> brought up wrong, with an emphasis on convergence> in norm instead of pointwise convergence - I'm not> going to tell you how old I was the day I got that> strange look from a colleague after revealing I> didn't even realize that the integral of s had> anything to do with the FT...)>> Well done David! I hope Mr Boschma now realizes> all the little details he's sweeping under the carpet ... :-)>Still, it's possible he answered the question OP asked, which might beassuming all the details you mathematicians worry about, how do I calculatethe answer I need for my engineering calculations. In other words, (Ihope) I took a course once where I saw this proved, so I know it's true, Ijust need to know how to calculate to get the answers I need. Rather thanthe (I fear) I don't care about the math, I just need the answer.Jon Miller out? = >> integral from 0 to in'nity of sin(x) / x is pi/2.>> What sould I do to calculate out this result?> Use Fourier transform, very easy. Quick outline, all sorts of constants> are not considered here:>> If f(t) is de'ned as: f(t) = 0, |t| > 1> f(t) = 1, |t| <= 1>> then its Fourier transform F(w) is of the form sin(w)/w (see lookup> tables...):>> +infty 1> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt> -infty -1 j? The transform back is de'ned by:>> +infty> f(t) = 1/(2pi) INT F(w) exp(jwt) dw> -infty De'ned by, or is? Of course, in our case F is not an L_1 function> and so one has to be careful about these improper limits.> Incidentally, in this case, is your formula true for t = 1? I seem to remember from my undergraduate days> that the proof we saw of the Fourier inversion theorem> was dependent on the identity pi/2 = integral_0^in'nity sin(x)/ x dx. Could you outline a proof of the Fourier inversion theorem,> valid pointwise (under suitable hypotheses) not using this identity?> I'm sorry, like Phil already detected I'm just an engineer (with my owndialect) and not being a native speaker also contributes to sloppy useof Ois de'ned by' or whatever is mathematically more consistent. SinceI also forgot a lot of what I learned at university, I do not have theproof available (if it exists...) you request. I have to look it up inthe books, but you can do that also. Jeroen> --> Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.html> Needless to say, I had the last laugh.> Alan Partridge, _Bouncing Back_ (14 times) = >> Could you outline a proof of the Fourier inversion theorem,>> valid pointwise (under suitable hypotheses) not using this identity?> I'm sorry, like Phil already detected I'm just an engineer (with my own> dialect) and not being a native speaker also contributes to sloppy use> of Ois de'ned by' or whatever is mathematically more consistent. Since> I also forgot a lot of what I learned at university, I do not have the> proof available (if it exists...) you request. I have to look it up in> the books, but you can do that also.So, your answer is no.-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) out? = >> Could you outline a proof of the Fourier inversion theorem,>> valid pointwise (under suitable hypotheses) not using this identity?>> I'm sorry, like Phil already detected I'm just an engineer (with my own> dialect) and not being a native speaker also contributes to sloppy use> of Ois de'ned by' or whatever is mathematically more consistent. Since> I also forgot a lot of what I learned at university, I do not have the> proof available (if it exists...) you request. I have to look it up in> the books, but you can do that also. So, your answer is no.> It is! But just saying no sounds a bit rude to me...> --> Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.html> Needless to say, I had the last laugh.> Alan Partridge, _Bouncing Back_ (14 times) it out? => integral from 0 to in'nity of sin(x) / x is pi/2.>> What sould I do to calculate out this result?> Use Fourier transform, very easy. Quick outline, all sorts of constants> are not considered here:>> If f(t) is de'ned as: f(t) = 0, |t| > 1> f(t) = 1, |t| <= 1>> then its Fourier transform F(w) is of the form sin(w)/w (see lookup> tables...):>> +infty 1> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt> -infty -1>> j?Engineering dialect for i.-- P.A.C. SmithThe vast majority of Iraqis want to live in a peaceful, free world.And we will 'nd these people and we will bring them to justice. it out? => +infty 1> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt> -infty -1>>j? Engineering dialect for i.I always thought it was exclusive to *Electrical*engineering, to avoid confusing i with electricalcurrent (Amps).Carlos-- it out? =>> +infty 1> F(w) = INT f(t) exp(-jwt) dt = INT exp(-jwt) dt> -infty -1>>j?>> Engineering dialect for i.>> I always thought it was exclusive to *Electrical*> engineering, to avoid confusing i with electrical> current (Amps).Isn't that I?-- P.A.C. SmithThe vast majority of Iraqis want to live in a peaceful, free world.And we will 'nd these people and we will bring them to justice. it out? => integral from 0 to in'nity of sin(x) / x is pi/2.> What sould I do to calculate out this result?First work out the integral from -oo to +oo by considering the integral ofexp(iz)/z on the contour formed by:(i) The real axis from -R to -e and e to R;(ii) The semicircle |z| = e in the upper half-plane;(iii) The semicircle |z| = R in the upper half-plane;using the residue calculus for (ii) and the total contour, Jordan'slemma for (iii), and taking the limit as e -> 0 and R -> oo.-- P.A.C. SmithThe vast majority of Iraqis want to live in a peaceful, free world.And we will 'nd these people and we will bring them to justice. =>> integral from 0 to in'nity of sin(x) / x is pi/2.> What sould I do to calculate out this result?>> First work out the integral from -oo to +oo by considering the integral of> exp(iz)/z on the contour formed by:>> (i) The real axis from -R to -e and e to R;> (ii) The semicircle |z| = e in the upper half-plane;> (iii) The semicircle |z| = R in the upper half-plane;>> using the residue calculus for (ii) and the total contour, Jordan's> lemma for (iii), and taking the limit as e -> 0 and R -> oo.That is a nice textbook solution. I was just wandering, is there a simpleway to evaluate the integral without using residues?-Michael. = That is a nice textbook solution. I was just wandering, is there a simple> way to evaluate the integral without using residues?Yes.Prove thatpi/2 = integral_0{pi/2} sin ((2n+1)y)/sin y dySet I_n = integral_0^{(2n+1)pi/2} sin x/x dx= integral_0^{pi/2} sin((2n+1)/y)/y dy.Using these integral representations, prove that|pi/2 - I_n| -> 0 as n -> in'nity. (BasicallyRiemann-Lebesgue applied to y |-> 1/y - 1/sin(y)).-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) => By the time I saw your response to my other post, I have already>replied to this post of yours. I would not have otherwsie.>>Put it in your think head. You cannot demand; you can only request. HUH?!> New technology: read head, write head, erase head, think head.As it's Monday morning mine feels mostly like the third in the list. =>> By the time I saw your response to my other post, I have already>>replied to this post of yours. I would not have otherwsie.>>Put it in your think head. You cannot demand; you can only request.>> HUH?!>New technology: read head, write head, erase head, think head.Ahh!! That explains the idiocy. Empty head, then think.>>As it's Monday morning mine feels mostly like the third in the list. In our biz, we called it refreshed. That was what youdid to a disk when it had lots of lost blocks or bad spots oryou were creating a new system disk. Another option was destroy./BAH =>> 3 Africans I met in Computer science department in the last 4>>years were way above average in thier programming skills in>>the midst of Chinese and Indian grad students who are the>>overwhelming majority in that department.>>You will always 'nd bright smart people in just about any >> naturally>>occuring group of humans. Race is nothing. Culture is everything.>>Bob Kolker>>That's my point.>>What point? Culture Shmulture....that is simplistic politically >> correct>>heurist bull of the 'rst kind. >>No, it is not.>If it were that simple >>It is THAT simple where I grew up. >>Children in the poor neighborhood with their parents making ends meet>and the children having to do the house work like an adult and start>working while they themslevs are children (rather than play or study,>do not get a chance to test their brain since there is no books (not>referring to school text books and notes) lying around the house.>>That's a lot of bull. House work (or farm work) is so boring>one has nothing else to do but think. It also gives one an incentive>to go to school and study real hard so that one can get a job that>doesn't involve either. >> Afriend of mine from Wisconsan said justt hat.>> He had to get up and helped his father milk the cows in the farm and>>it was boring for him. He became a programmer. It was possible for him>>because he is the this US of A.>> A country which was built by people. Nobody gave them anything;>> they did the work themselves. Since you want us to believe that>> you are from an underprivileged country that contains no books,>> no schools, no business opportunities, I suggest that you begin>> to work to build an infrastructure. However, since you're complaining>> about having to do housework from dawn to dusk, I conclude that>> there exist people who are able to hire other people to clean.>> That implies that they make the money they pay those housecleaners>> in some other industry than housecleaning. Thus, that country>> has opportunities available for thousands.>>Can you read well? Some days I read very well, including in between the lines.>>When did I ever say I had to work from dawn to dusk? First of all, I>wasn't talking about myself.Then your comments were not based on experience but on yourhypothesis of what poor people cannot do.> .. Secondly, here is how my day started.>Get up, brush my teeth and wash my face. Have breafast which was>already on the the table. Get ready for school. Grab my lunch box and>go wait for school bus which arrives around 8:20Am.>>School starts at 9:15 and releaseed at 3:15. That was one of your problems. That's only 4-5 hours of class timeper day.>>School bus brought me home. Change my clothes. Have some snack and>wait for my Math tutor (not everyday; in that case, I did my Math>homework, the only homework I was keen to do). Have dinner around 6.>Then , it varies how my day ends. That was 6th grade. In 7th garde,>my Math tutoring moved to 7Am till 8:30 in the morning and so I had to>catch the school bus when it came around the senodn time by walking to>a friend's house on the next block. In 8th grade, it was after school.>So on.>>Now, say that I was spoiled or privileged. Yup. You didn't have to work and earn money.> ..But notice that there>wasn't extracurricular activites sponsored by school like during my>older siblings time. You poor baby. You were so underprivileged.> ..They went to Private schools (founded during>British time) which did not exist anymore in my time. That's because>there was no budget for it except for short term ones, which I joined>some times.Heaven forbid that you or your parents pay for extracirricular activities rather than forcing the rest of the population pay for your bidding.>>I did learn swimming one summer at a private place. But before 7th>grade, i.e when we were not old enough to be rebellious, in summer, my>mother would teach us.>>With college education during my time, unlike my oldest sister's time,>I would not qualify to be considered privileged. I wasn't complaining>about that.>About your telling me I suggest that you begin> to work to build an infrastructure., I tell you this: stay within>the context of diuscussion and ...>> ..do not act so dumb not to know that there are countries where>people are not free to do (build) their infrastructure. But mostly,>just stay within the context, will you?I've been trying to stay within context.>Housework is a very good lesson in >eliminating some choices of employment. >>Not for those who is left with no time to study when it is not just>>helping around the house with chores.>> Excuse me? Housework has ample opportunity for study. Since it>> takes no thinking (or not much) to vacuum or wash a §oor, one>> can use their brains to learn at the same time. >I would set a book>> up, read a paragraph, and think about it while doing other work.>> If I still hadn't got it, I would read it again and continue doing>> the physical work. When I 'gured it out, I would read the next>> part of the text. In the computer biz, we called this §avor>> of doing many things at once, timesharing.> Well..I never was so keen to study like a bookworm. That just means that you were not motivated to learn. Youclaimed that poor people who did housework didn't have anyaccess to books; thus, those who did have high IQs wouldnever be allowed to learn beyond housework jobs.>the point was that I was NOT talking about me. I was talking about>the kids from the poor family.Which you also don't have a clue about. I also was talking aboutkids and adults who don't have lots of money.> . Do you know how poor family lives in>3rd world countries? Obviosuly not.yes, I have some idea. I also know how poor families live inthe US.>Public libraries? You seem to think that all countries have good>>public libraries.>> This thread was talking about US schools and such.>No it was not. It was about Asians. IIRC, the thread drifted to the question about why Asians didwell in US schools. Now, you tend to commit continental drift.Which Asians (Asia is a very big place) were referencing?China has a system in place that detects gifted kids and provideslearning opportunities to those kids (and the majority of Chineseare poor according to your standards). Did you want to talk aboutanother place?>In fact, Josh halpern's reply was enough. I shouldn't even have>bothered to reply to you. You were so way out of the context of the>topic in discussion.When you name drop, you should be choosy./BAH =>> 3 Africans I met in Computer science department in the last > 4>>years were way above average in thier programming skills in>>the midst of Chinese and Indian grad students who are the>>overwhelming majority in that department.>>You will always 'nd bright smart people in just about any > naturally>>occuring group of humans. Race is nothing. Culture is > everything.>>Bob Kolker>>That's my point.>>What point? Culture Shmulture....that is simplistic politically > correct>>heurist bull of the 'rst kind. >>No, it is not.>If it were that simple >>It is THAT simple where I grew up. >>Children in the poor neighborhood with their parents making ends > meet>and the children having to do the house work like an adult and start>working while they themslevs are children (rather than play or > study,>do not get a chance to test their brain since there is no books (not>referring to school text books and notes) lying around the house.>>That's a lot of bull. House work (or farm work) is so boring>one has nothing else to do but think. It also gives one an incentive>to go to school and study real hard so that one can get a job that>doesn't involve either. >> Afriend of mine from Wisconsan said justt hat.>> He had to get up and helped his father milk the cows in the farm and>>it was boring for him. He became a programmer. It was possible for him>>because he is the this US of A.>> A country which was built by people. Nobody gave them anything;>> they did the work themselves. Since you want us to believe that>> you are from an underprivileged country that contains no books,>> no schools, no business opportunities, I suggest that you begin>> to work to build an infrastructure. However, since you're complaining>> about having to do housework from dawn to dusk, I conclude that>> there exist people who are able to hire other people to clean.>> That implies that they make the money they pay those housecleaners>> in some other industry than housecleaning. Thus, that country>> has opportunities available for thousands.>>Can you read well? Some days I read very well, including in between the lines.>When did I ever say I had to work from dawn to dusk? First of all, I>wasn't talking about myself. Then your comments were not based on experience but on your> hypothesis of what poor people cannot do. It was basee on seeing children selling things (eg. cigarettes) onthe roadside.> .. Secondly, here is how my day started.>Get up, brush my teeth and wash my face. Have breafast which was>already on the the table. Get ready for school. Grab my lunch box and>go wait for school bus which arrives around 8:20Am.>>School starts at 9:15 and releaseed at 3:15. That was one of your problems. That's only 4-5 hours of class time> per day. Class time may be 4-5 hours (school was released at 3:45pm, I forgot)but it was not bull teaching like in your publich schools.Besides, my mother taught us so much that we thought we were inprison, never getting enough time to play. (One of my brothers got toskip Kindergarten just from her teaching; that option was not availabein my time). We would literally hide from her sight but she wouldalways call out our names, and one better be obedient. Then wereached the age where she got private tutors teaching us. Among thesubjects was Arabic, staring at age 5. Don't ask me to elaborate.>School bus brought me home. Change my clothes. Have some snack and>wait for my Math tutor (not everyday; in that case, I did my Math>homework, the only homework I was keen to do). Have dinner around 6.>Then , it varies how my day ends. That was 6th grade. In 7th garde,>my Math tutoring moved to 7Am till 8:30 in the morning and so I had to>catch the school bus when it came around the senodn time by walking to>a friend's house on the next block. In 8th grade, it was after school.>So on.>>Now, say that I was spoiled or privileged. Yup. You didn't have to work and earn money. There was nothing wrong with that since when the time came for me todo it (after getting to US), I could do it. ..But notice that there>wasn't extracurricular activites sponsored by school like during my>older siblings time. You poor baby. You were so underprivileged. Is that all you can say? ..They went to Private schools (founded during>British time) which did not exist anymore in my time. That's because>there was no budget for it except for short term ones, which I joined>some times. Heaven forbid that you or your parents pay for extracirricular > activities rather than forcing the rest of the population pay > for your bidding. The sentence was meant to refer public school in our time (undermilitary rle) not having budget. I addedd a sentence in the middle andhence looking like I was talking about extracurricular activites. Butthen again, whatever few activites available, one better can affordthe supplies.On the other hand, my grandfather donated so much to the school thathis children were in (sometimes paying for the whole X'Mas party), itwas practically as if he was paying for those activites. But then hewas a rich and powerful man in his time and it was expaected that hedid that.>>I did learn swimming one summer at a private place. But before 7th>grade, i.e when we were not old enough to be rebellious, in summer, my>mother would teach us.>>With college education during my time, unlike my oldest sister's time,>I would not qualify to be considered privileged. I wasn't complaining>about that.>About your telling me I suggest that you begin> to work to build an infrastructure., I tell you this: stay within>the context of diuscussion and ...>> ..do not act so dumb not to know that there are countries where>people are not free to do (build) their infrastructure. But mostly,>just stay within the context, will you? I've been trying to stay within context.>>Housework is a very good lesson in >eliminating some choices of employment. >>Not for those who is left with no time to study when it is not just>>helping around the house with chores.>> Excuse me? Housework has ample opportunity for study. Since it>> takes no thinking (or not much) to vacuum or wash a §oor, one>> can use their brains to learn at the same time. >>I would set a book>> up, read a paragraph, and think about it while doing other work.>> If I still hadn't got it, I would read it again and continue doing>> the physical work. When I 'gured it out, I would read the next>> part of the text. In the computer biz, we called this §avor>> of doing many things at once, timesharing.> Well..I never was so keen to study like a bookworm. That just means that you were not motivated to learn. Why would I need to keep reading school stuff like a bookworm when Ihad other books I could be reading (whether it was realated to schoolwork or not) when I already know the school material I needed to know?Is it possible for you to understand that for some people, especiallythe materials up till the end of high school are a piece of cake.Just because you have to repeatedly study the same material over andover again, it deosn't mean that everyone would need to do the samewayto achive learning. You are hopeless to keep insisitng that poor people could have accessto books if they want. Get out of your little world and see the worlda bit before you die, will you? > You> claimed that poor people who did housework didn't have any> access to books; thus, those who did have high IQs would> never be allowed to learn beyond housework jobs.Yes that's what happened. In this guy's case, it was farm works. Hecame from very remote rural area.He worked for my brother. He was in his 30s when we got to know him.He found my family and presented hismelf to be reliable andtrustworhty. The guy was very bright, in fact higly intelligent buthe could barely read or write.Because he was reliable and trustworthy AND bright, he got the job inmy brother's jewelry business. Despite no education, he 'tted rightin tot he extent that in time, all of us treated him like a familymember.. the point was that I was NOT talking about me. I was talking about>the kids from the poor family. Which you also don't have a clue about. That's your opinion. I said children from poor families... > I also was talking about> kids and adults who don't have lots of money.You are hopeless with no clue. Typical American who knows nothingabout the world beyond your borders. . Do you know how poor family lives in>3rd world countries? Obviosuly not. yes, I have some idea. I also know how poor families live in> the US. I was not talking about US. I was talking about MY country (I saidwhere I grew up) where there is no government programs for the poor.Even mandatory education requirement eatsbalished by law is notenforced. Somehow, the kids in the cities manage to be literate whilethe people in remote rural area joined short term programs (if theprograms come to their region; usually, goverment send those programsonly to areas where the Burman is a majority) to learn how to read andwrite as adults. >public libraries.>> This thread was talking about US schools and such.>No it was not. It was about Asians. IIRC, the thread drifted to the question about why Asians did> well in US schools. Now, you tend to commit continental drift.> Which Asians (Asia is a very big place) were referencing?Learn to read in context. China has a system in place that detects gifted kids and provides> learning opportunities to those kids (and the majority of Chinese> are poor according to your standards). Did you want to talk about> another place? I was not talking about China. Again, learn to stay within context.No amount of briging in more crap won't undo your status as a typicalaverage American. In fact, Josh halpern's reply was enough. I shouldn't even have>bothered to reply to you. You were so way out of the context of the>topic in discussion. When you name drop, you should be choosy.You are a Hopeless, Clueless, Typical Average American. If you want tochsnge that, may I suggest that you start with reading and listeningto news from sources other than your media. /BAH> =>> By the time I saw your response to my other post, I have already>>replied to this post of yours. I would not have otherwsie.>>Put it in your think head. You cannot demand; you can only request.>> HUH?!>>Did you have to use the word Of***ing'? >>You could have asked What countries were they from?And you still haven't answered the damned^W question./BAH =>> By the time I saw your response to my other post, I have already>>replied to this post of yours. I would not have otherwsie.>>Put it in your think head. You cannot demand; you can only request.>> HUH?!>>Did you have to use the word Of***ing'? >>You could have asked What countries were they from? And you still haven't answered the damned^W question.I am not obligated to answer, am I? /BAH> =>By the time I saw your response to my other post, I have already>replied to this post of yours. I would not have otherwsie.>>Put it in your think head. You cannot demand; you can only request.>>HUH?!>>Did you have to use the word Of***ing'? >>You could have asked What countries were they from?>> And you still haven't answered the damned^W question.>>I am not obligated to answer, am I?Gawd, I hate cute. Nope, you aren't obliged to answer,especially when you used the datum as the basisof your argument. When asked for a clari'cation of thatdatum, you deliberately ignore the question, add all kindsof red lines to divert the lack of an answer. Ergo, youdon't feel very strongly about the subject but do wantto get a free ride based on perceived discrimination./BAH =>>And you still haven't answered the damned^W question.> I am not obligated to answer, am I?That depends on whether you're the asker or answeree. =>When you run a race, you don't automatically award 'rst>>place to every runner.There were six hundred places. What is the difference between the 599th>person in that class and the 601st in terms of ability? The wonderprof>simply abdicated any responsiblity for educating the students. Quite>common.>Exactly. That is why a rational society only cares about win, place,>>and show rather than compassionately about a huge pool of>>incompetents.>>Uncle Al>>I wouldn't insist too strongly on your idea, Al. The treatment of the>incompetents has to be cared about by society, otherwise they,>or many of them, will come to your house and tell you to beat it>and kick your ass out without thought nor regrets.>>I sympathize with you that things should be as simple as you say.>But it just isn't in the cards. If it were that straight forward then>the solution would have been found long ago and would have >been practiced all over the place. Utopia would be at hand.>hanson>Actually they are very good at kicking ass, and Al knows allabout them, which explains much of his pain.josh halpern =Sure, the I don't fail you you fail you bull. He didn't>>educate anyone either. He didn't go out and get more>>resources for more students.>>When you run a race, you don't automatically award 'rst>place to every runner.>There were six hundred places. What is the difference between the 599th>>person in that class and the 601st in terms of ability? The wonderprof>>simply abdicated any responsiblity for educating the students. Quite>>common.>> about win, place,>and show rather than compassionately about a huge pool of>incompetents. >Right, by your own terms you lost the minute you didn'tgo to MIT or Cal Tech. Now go away and stop whining.josh halpern =>> populated by Asians and Jews with astounding credentials>> 'gure out how Asians and Jews can universally do so well.>> that was exactly how the Chinese students functioned.>What a mutual minority admiration society.......ahahahaha.....I've never seen before such a self exposee by some of/in the minorities about expressing their self-in§icted inferiority complex to such an extent, especially in the view that they could have hardly excelled to the extent they did and do were they in their own society of ethnic origin, or so they claim. Therefore, to alleviate the curse from this albatross that is hanging around their minds, I suggest:Sweet Amanda, ask macho Al to **donate** to your uterus a sample from his paid, applause garnishing 6 cc sperm donations.You two could spawn the superspecies' that the Nazis and the Jewish comic book authors of Superman had only orgasms in their dreams about.... You guys could bring this epic yearning to fruition and reality........for a better world.Christen...eh,..ah... no,no... just label your offspring as the long nosed slit eyed one, which in all probability will be his/her most pronounced features.> Indian students functioned similarly too.>Ooohh my gahhhhd, there's the nigger in the wood pile.Here are them Indians, Al, the ones you are so envious ofbecause they have, according to you, only some 10 §ush toilet on the entire sub-continent.This unfortunately means that you'll be able to produce anoffspring with only 2/3 rd of the max of the full potential thatthe human genome would allow.You jokers are nuts! But then, this is the Usenet, a 24/7 cyberparty, where prodigies that failed have to come to die.........Therefore, let'em sing.....all of them....it's a beautiful choir!ahahahah....ahahahahah...ahahahaha.....ahahahanson => You jokers are nuts! But then, this is the Usenet, a 24/7 cyber> party, where prodigies that failed have to come to die.........> Therefore, let'em sing.....all of them....it's a beautiful choir! Sig 'le!!!Usenet - where failed prodigies come to die.Mr. Shambat, how do you say that in Russian? => You jokers are nuts! But then, this is the Usenet, a 24/7 cyber> party, where prodigies that failed have to come to die.........> Therefore, let'em sing.....all of them....it's a beautiful choir!>> Sig 'le!!!bob, are you a wanna-be or closet Nazi? ........anyway, Bob, it would be Sieg Heil.>> Usenet - where failed prodigies come to die.> Mr. Shambat, how do you say that in Russian?>I don't know about any Mr. Shambat,but to play with or to shave her Schambart, THAT is a lovely thing.ahahaha.....ahahahanson =>> populated by Asians and Jews with astounding credentials>> 'gure out how Asians and Jews can universally do so well.>> that was exactly how the Chinese students functioned.> What a mutual minority admiration society.......ahahahaha..... I've never seen before such a self exposeeI don't function with your standard Hanson. Your standard == I won'texpose the dirty things my group does.Beside, I was never a part of any group. I was always minortity amongminortities but that is not the reason I tell it like it is.Even within my family, I always get into trouble because I speak thetruth but no one will change my nature. I am me and am happy aboutit.> by some of/in the > minorities about expressing their self-in§icted inferiority complex > to such an extent, especially in the view that they could have > hardly excelled to the extent they did and do were they in their > own society of ethnic origin, or so they claim. I don't know about self-inferiority complex blah..blah..blah but youspelled out what I wanted to say, i.e if it were not for their stronggroup, neither Chinese nor Indians will dominate in science programsin grad school. They know that too but still some had the nerve to actsnobbish. Aside form all that, I did not convey that none of themwould have excelled to the extent they did in those programs if theyhave to do it alone. As far as doing it in their own society of ethnicorigin, I said nothing about it. I think that you are just grabbing my post as an excuse to spew outthe garbage you have wanted to spew for a long time.> Therefore, to alleviate the curse from this albatross that is > hanging around their minds, I suggest: Sweet Amanda, ask macho Al to **donate** to your uterus a > sample from his paid, applause garnishing 6 cc sperm donations.> You two could spawn the superspecies' that the Nazis and the > Jewish comic book authors of Superman had only orgasms in > their dreams about.... You guys could bring this epic yearning to > fruition and reality........for a better world.> Christen...eh,..ah... no,no... just label your offspring as the > long nosed slit eyed one, which in all probability will be his/her > most pronounced features. I know your kind Hanson. You will collaborate with whoever is winningat the moment, be it Chinese or Indians, just to make a buck. Indian students functioned similarly too.> Ooohh my gahhhhd, there's the nigger in the wood pile.> Here are them Indians, Al, the ones you are so envious of> because they have, according to you, only some 10 §ush toilet > on the entire sub-continent.> This unfortunately means that you'll be able to produce an> offspring with only 2/3 rd of the max of the full potential that> the human genome would allow. You jokers are nuts! But then, this is the Usenet, a 24/7 cyber> party, where prodigies that failed have to come to die.........> Therefore, let'em sing.....all of them....it's a beautiful choir! ahahahah....ahahahahah...ahahahaha.....ahahahanson => I know your kind Hanson. You will collaborate with whoever> is winning at the moment, be it Chinese or Indians,> just to make a buck.>Amen!> ahahahah....ahahahahah...ahahahaha.....ahahahanson => I know your kind Hanson. You will collaborate with whoever> is winning at the moment, be it Chinese or Indians,> just to make a buck.> Amen! ahahahah....ahahahahah...ahahahaha.....ahahahanson .. just to make a buck at the expense of truth and facts. If all the energy you used in writing your granage on regular basiscould be used in .. Never mind. You are not capable to do that. => I know your kind Hanson. You will collaborate with whoever> is winning at the moment, be it Chinese or Indians,> just to make a buck.>> Amen!>> .. just to make a buck at the expense of truth and facts.>Amen!.... just because your truth ain't fact and your facts ain't true.ahahahah....ahahahahah...ahahahaha.....ahahahanson => I know your kind Hanson. You will collaborate with whoever> is winning at the moment, be it Chinese or Indians,> just to make a buck.>> Amen!>> .. just to make a buck at the expense of truth and facts.>> Amen!> .... just because your truth ain't fact and your facts ain't true. ahahahah....ahahahahah...ahahahaha.....ahahahansonGo take your med, really! => I know your kind Hanson. You will collaborate with whoever> is winning at the moment, be it Chinese or Indians,> just to make a buck.>> Amen!>> .. just to make a buck at the expense of truth and facts.>> Amen!> .... just because your truth ain't fact and your facts ain't true.>> Go take your med, really!>So,...... you wanna play doctor with me now, after you have failed miserably in politics, sociology, psychology, philosophy & economics?..........AHAHAH.....ahahahaha...... Babe, listen, you are not very successful, except when it comes to nagging and whining....about YOUR own problems.......ahahahahaha....ahahahah....ahahahahah... ahahahaha.....ahahahanson => So,...... you wanna play doctor with me now, after you have failed > miserably in politics, sociology, psychology, philosophy & economics?> ..........AHAHAH.....ahahahaha...... Babe, listen, you are not very > successful, except when it comes to nagging and whining> ....about YOUR own problems.......ahahahahaha....> ahahahah....ahahahahah...ahahahaha.....ahahahansonHaving a woman volunteer to play doctor is bad? Howzzat???? = > So,...... you wanna play doctor with me now, after you have failed > miserably in politics, sociology, psychology, philosophy & economics?> ..........AHAHAH.....ahahahaha...... Babe, listen, you are not very > successful, except when it comes to nagging and whining> ....about YOUR own problems.......ahahahahaha....> ahahahah....ahahahahah...ahahahaha.....ahahahanson Having a woman volunteer to play doctor is bad? Howzzat????Ilsa: SS Doctor =>So,...... you wanna play doctor with me now, after you have failed >miserably in politics, sociology, psychology, philosophy & economics?>..........AHAHAH.....ahahahaha...... Babe, listen, you are not very >successful, except when it comes to nagging and whining>....about YOUR own problems.......ahahahahaha....>ahahahah....ahahahahah... ahahahaha.....ahahahanson>>Having a woman volunteer to play doctor is bad? Howzzat????> Ilsa: SS DoctorNews§ash: Ilsa does not qualify as a woman. Female,perhaps. => hanson [ retorted to a woman, not you, Bill, > [ sheesh, you're too old and ugly.....ahahaha..]: So,...... you wanna play doctor with me now, after you have failed > miserably in politics, sociology, psychology, philosophy & economics?> ..........AHAHAH.....ahahahaha...... Babe, listen, you are not very > successful, except when it comes to nagging and whining> ....about YOUR own problems.......ahahahahaha.... ahahahah....ahahahahah...ahahahaha.....ahahahanson> [Bill]> Having a woman volunteer to play doctor is bad? Howzzat????> .....with all her nagging and bitching? .....ahahahahhaa..........I doubt that even a superb dictation, nor much less a profound recti'cation will keep her quiet and make her happy. And in case of her having keen oral interests, even such a notorious machinationwill not keep her occupied in silence and solace for long neither. Do you have any advanced ideas, Bill, to bring inner peace to thatpoor and agitated woman? We must be good Samaritans, don't we?ahahahaha........ahahahahanson...... =>>hanson [ retorted to a woman, not you, Bill, >>[ sheesh, you're too old and ugly.....ahahaha..]:>So,...... you wanna play doctor with me now, after you have failed >miserably in politics, sociology, psychology, philosophy & economics?>..........AHAHAH.....ahahahaha...... Babe, listen, you are not very >successful, except when it comes to nagging and whining>....about YOUR own problems.......ahahahahaha....>ahahahah....ahahahahah... ahahahaha.....ahahahanson> [Bill]>>Having a woman volunteer to play doctor is bad? Howzzat????> .....with all her nagging and bitching? .....ahahahahhaa..........> I doubt that even a superb dictation, nor much less a profound > recti'cation will keep her quiet and make her happy. And in case > of her having keen oral interests, even such a notorious machination> will not keep her occupied in silence and solace for long neither. > Do you have any advanced ideas, Bill, to bring inner peace to that> poor and agitated woman? We must be good Samaritans, don't we?> ahahahaha........ahahahahanson......Paci'cation is just around the corner in Amanda's case. In factI think it an easily achievable goal. In general, I think passiona good thing. If I'm wrong in everything else in this exchange, Ido know she's given some very good replies.Keeping true to your persona, don't fret over it. There's room forall of this in sci.physics. =>populated by Asians and Jews with astounding credentials>'gure out how Asians and Jews can universally do so well.> that was exactly how the Chinese students functioned.hanson, take yours meds. you were improving.josh halpern>What a mutual minority admiration society.......ahahahaha.....>>I've never seen before such a self exposee by some of/in the >minorities about expressing their self-in§icted inferiority complex >to such an extent, especially in the view that they could have >hardly excelled to the extent they did and do were they in their >own society of ethnic origin, or so they claim. >Therefore, to alleviate the curse from this albatross that is >hanging around their minds, I suggest:>>Sweet Amanda, ask macho Al to **donate** to your uterus a >sample from his paid, applause garnishing 6 cc sperm donations.>You two could spawn the superspecies' that the Nazis and the >Jewish comic book authors of Superman had only orgasms in >their dreams about.... You guys could bring this epic yearning to >fruition and reality........for a better world.>Christen...eh,..ah... no,no... just label your offspring as the >long nosed slit eyed one, which in all probability will be his/her >most pronounced features.>>Indian students functioned similarly too.Ooohh my gahhhhd, there's the nigger in the wood pile.>Here are them Indians, Al, the ones you are so envious of>because they have, according to you, only some 10 §ush toilet >on the entire sub-continent.>This unfortunately means that you'll be able to produce an>offspring with only 2/3 rd of the max of the full potential that>the human genome would allow.>>You jokers are nuts! But then, this is the Usenet, a 24/7 cyber>party, where prodigies that failed have to come to die.........>Therefore, let'em sing.....all of them....it's a beautiful choir!>>ahahahah....ahahahahah...ahahahaha.....ahahahanson => hanson, take yours meds. you were improving.Recently he's been better than ever, whatever thereason. Keep it up, I say. => hanson, take yours meds. you were improving. Recently he's been better than ever, whatever the> reason. Keep it up, I say.>since everything is up and running. Nevertheless, your kind words are balsam for my soul. You are a good man, Bill......on the other hand..... for Josh I have a warm spot in my heart too , despite hisonly major §aw, which is his seeing the world thru toomuch green tint, which make him extrude and expeloccasionally green turds, precipitating his bigger thanlife brooding seriousness. But, the fact that Josh was notcapable to post his 7 words above in the best grammartradition, that I will not hold against him. The faux pas of Josh's gauche literary ejaculation may have been precipitated because it happened on a Saturdayevening, while he was gargling copiously with cheap CA wine, which made him miss the joke or perhaps his EtOH decripition didn't let him get the joke........ahahahaha....Things like that can and do happen and this appears tobe really one of Josh's endearing qualities, in that he takes everything so serious. One of the 'rst time I conversed with him over NG's he asked me why I did/said something, to whichI responded that one of the priorities in my life was to pissoff everybody......to which Josh retorted with a serious andearnest, admonishmental sermon......which made me ROTL.It was then that I began to watch Josh because I am hoping to 'nd a ghost, a dear ghost, a buddy of yore, of a long time ago, a friend I have lost track of. I am hoping to 'nd a JoshHalpern who called himself JoHal. --- Is that you Josh? Your posting manners have a lot in common with JoHal's. --- If so, then 'll in and post, for ID purposes, the questions described in the following events .Nam. We got between the 101(?) and ARVN (when, whereJoHal ?). -- The gooks' mortars were pounding, pinning us down but you had to take a . Pants down, you stood up and shook your 'sts against the old A16's that camein laying down napalm, you shouting on top of your voice: For that , the ing govt has money... but to give me toilet paper, for my , I have to write a requisition.I'll always remember that, JoHal, ---- Still ROTFL and feelingthe taste of the earth in my mouth --- still thinking about that ing game of so long ago, a time of long periods of total, excruciating boredom pierced by a few moments or minutes of sheer and absolute terror and near terminal adrenaline shock. Salvage Operations, (was it Bora-Bora, Tahiti, Rara-Tonga, Pelelu, which?) when we 2 had that gig, that memorablegang bang with the 2 big boobed French AC/DC bulldikes, happened there and where ....ahahahahaha.... if you Josh are 2 BB was incessantly humming Edith Pilaf's those were the daysmy friend... hope they will never end ........and then in typicalJoHal fashion of superb sense of seriousness and commitmentyou wanted to marry both, the 2 of them, because they had aprofound love of life............I still ROTF thinking about that.I hope that you are JoHal and answer. If you ain't then maybesomebody may know of/about JoHal about whom I last heard that he went precious opal mining in Australia's outback butsomewhere the hit the fan and they allegedly threw himinto a mine shaft followed by a bundle of dynamite... How did you get out of this one, JoHal? Did you fake your own demise?I wouldn't put it past you. But stop worrying. Everything is now way past all statutes of limitations. Come on, show up, for we still have some un'nished, grand biz to accomplish, undun remants from those years of stark terror and silly ecstasies. That was life, big time! ..... I am hoping, dude,.....hanson,........ kk57v5....alpha-charly-tango....over...... =hanson, take yours meds. you were improving.Recently he's been better than ever, whatever the>>reason. Keep it up, I say.since everything is up and running. Nevertheless, your kind >words are balsam for my soul. You are a good man, Bill.>>.....on the other hand..... >to troll the troll or not to troll the troll; that is the question. whethertis' better to endure the slang and grammar arrows from anunder medicated troll, or simply to plonk.....ah bless'd delete keyjosh halpern =>hanson, take yours meds. you were improving.>Recently he's been better than ever, whatever the>>reason. Keep it up, I say.>>since everything is up and running. Nevertheless, your kind >words are balsam for my soul. You are a good man, Bill.>>.....on the other hand..... > to troll the troll or not to troll the troll; that is the question. > whether tis' better to endure the slang and grammar arrows from an> under medicated troll, or simply to plonk.....ah bless'd delete key> josh halpernWell, Josh, I am so sorry to hear that you are not JoHal. But, for the consolation price you offered in admitting that it cranked enormously, I must truly thank you...............AND.... on the other hand..........is it perhaps not me, but the hellgrammites that are still active within your cranium? It's only Sunday morning...and your metabolism slows with age, buddy,ahahahaha....ahahahahahanson = Speaker: William Wertz on Schiller: Poet of Freedom. Schiller, poet of Romantic Dreck. > Have your read the words to -Ode an die Freude-?> Bob Kolker>This poem from Schiller and Mileva's know-how were Einstein'shis Christian wife, Mileva Maric, over and over again...until he dumped her, right after she had put HER ideas into writingand gave it to her hubby. This, HER work, which Albert published, without HER name on it, was his 1905 paper on special relativity.Speicher and such, will get a hernia and a pile of hemmies whenthey hear that, but a recent 1 hrs PBS show really insinuated that.Belief survey says: Jews: 100% false - Goyim: 100% true AHAHAHAHAH.........ahahahaha.......ahahahanson => The LaRouche Show is a weekly audio talk show, broadcast live on the> Internet every Saturday, featuring interviews with Lyndon LaRouche,> his associates, and special guests. Hosted by Michele Steinberg,> Counterintelligence co-director of Executive Intelligence Review, and> by Marcia Merry Baker, EIR Economics Intelligence director.> Live Broadcast TODAY> 3:00-4:00 p.m. Eastern Standard Time (2000-2100 UTC)> Speaker: William Wertz on Schiller: Poet of Freedom.> During the live broadcast, you can ask questions by calling one of the> following numbers:>> been practiced all over the place. Utopia You are a good man.Unfortunately (a), I have no time for Lyndon LaRouche, other when he comes on really big on the networks, usually every 4 years for 1 hr on the eve of the presidential elections. If you, his disciple, havemore in§uence on LaRouche, your role model and idol, then does his janitor, then please tell him to spread his message with a weee bit during his delivery his is depressing and bulimic. Unfortunately (b), in your condition and zeal you probably did hope for me to be this gent here, http://www.marvunapp.com/Appendix/cobrajal.htm#Hansonwhich would account for your wild guess and association, but.....Unfortunately (c), its is just re§ecting your own blossoming paranoia.ahahahahaha.......ahahahanson => amanda grava .88 la saucisse et au marteau:> [SNIP] Could you *please* the lines you are not responding to. Otherwise, this> is very hard and unpleasant to read and, besides, it takes more time to> download (and it's signi'cative with a low-speed modem).Well..when I used to do that (not in this group though), I was accusedof leaving out the info to mislead the reader, etc. Anyway, I am very sorry. I will do that from now on. =amanda grava .88 la saucisse et au marteau:> Well..when I used to do that (not in this group though), I was accused> of leaving out the info to mislead the reader, etc.Both can be done. You can quote some of the lines to make your answerunderstandable for someone who did not see the previous post, but stilldeleting the others.> Anyway, I am very sorry. I will do that from now i;@/WO(?;[KC9sW;wG/4@H[_VFFH4?QHJ#O(?m}7fQMrJ,]0THA'|e-EPG_> 56Mi}_RRhBS'a2}u_7jm)0_+'=$V#E2r4#IQE/d)yMv3_4 @hl<)mA&*tDN/ =In sci.math, Nicolas Le Roux:> amanda grava .88 la saucisse et au marteau:> [SNIP] Could you *please* the lines you are not responding to.Erm...are you sure you didn't inadvertantly snip the word snip?Pleasing the lines sounds impossible; I've never quite 'guredout whether chocolates or §owers will make the sentence This statement is falsehappy.:-) ;-) :-)> Otherwise, this> is very hard and unpleasant to read and, besides, it takes more time to> download (and it's signi'cative with a low-speed modem).> I can relate to that to some extent; I've a 56k myself. Fortunately,I also use leafnode (fetchnews) -- though that doesn't do a thingfor having to pay by the connection minute.-- #191, ewill3@earthlink.netIt's still legal to go .sigless. = grava .88 la saucisse et au marteau:> Could you *please* the lines you are not responding to.> Erm...are you sure you didn't inadvertantly snip the word snip?Actually, as far as I remember, I think it was the word delete.-- NicolasWow, THAT'S i;@/WO(?;[KC9sW;wG/4@H[_VFFH4?QHJ#O(?m}7fQMrJ,]0THA'|e-EPG_> 56Mi}_RRhBS'a2}u_7jm)0_+'=$V#E2r4#IQE/d)yMv3_4 @hl<)mA&*tDN/ =In sci.math, Nicolas Le Roux:> grava .88 la saucisse et au marteau:> Could you *please* the lines you are not responding to. Erm...are you sure you didn't inadvertantly snip the word snip? Actually, as far as I remember, I think it was the word delete.> Close enough. :-)-- #191, ewill3@earthlink.net -- insert random word hereIt's still legal to go .sigless. => Do you really mean>> C_i is also joined to C_{i-3} and C_{i+2} (subscripts read mod 7),no> or>> C_i is also joined to C_{i-2} and C_{i+2} (subscripts read mod 7),> ?yes-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) =In my previous thread, there seemed to be a general lack of consensuswith regard to whether algebraists implicitly invoke a functor whenthey say If G is a group, let G_e be its identityMore generally, if something is de'ned in such a way that it mustpossess something else (as, for instance, a group having to have anidentity, by the very de'nition of a group), it seems to me that thatdoes not mean we are no longer using a hidden function/functor when wecall up that something else.It is largely a matter of notation. Suppose mathematical notationwere de'ned in such a way that, when it was clear by context, wecould use the phrase its' square instead of x^2, as, for instance:Let x be a real greater than 1. Then x < its' squareWe are not used to such weird notation. But in more down-to-earthnotation, we say x < x^2, and I believe you will agree that we arethus implicitly using the function f(x)=x^2.How, then, is it any different to say,Let G be a group. Then G's identity is in GHere the culprit is the phrase G's identity. The way I see it, thisis the same as using a functor implicitly, just like its' [x's]square.Suppose we explicitly de'ned the functorI(g) = the identity of G. Then our above statement could be rewordedLet G be a group. Then I(G) is in GHere, we are explicitly using a functor (you won't deny that much!). But if we are not using one in the original phrase, then where did itcome from and where does it go? What I am saying is, the twostatements are the same exact thing. Therefor, since one uses thefunctor, both do.I am not trying to stir up trouble, just trying to get a grasp ofthese abstract things and very much eager for the help that youradvanced mathematical knowledge will no doubt shed upon the murkysubject.Sniz Pilbor =[cu]> It is largely a matter of notation. Suppose mathematical notation> were de'ned in such a way that, when it was clear by context, we> could use the phrase its' square instead of x^2, as, for instance: Let x be a real greater than 1. Then x < its' square We are not used to such weird notation. But in more down-to-earth> notation, we say x < x^2, and I believe you will agree that we are> thus implicitly using the function f(x)=x^2.I don't agree that we are implicitly using the function f(x) = x^2.The x^2 in x < x^2 is an element (I assume) in the natural numbers.I am not sure what of many ways you could be interpreting x^2 asimplictly using the function f(x) = x^2.Consider the situation where I de'ne the function f to bethe subset of NxN such that f = { (a,b) in NxN | a in N and b = a*a}.That last a*a cannot be implicitly using the function fsince I am de'ning it (ie f). Otherwise, the de'nition of f wouldbe circular.Just because you could replace my use of x^2 by referring tothe explicit use of the funciton f(x) = x^2 does not mean thatyou must be doing it implicitly. Sometimes there is an advantageto putting a particular situation into a more general context,but that does not mean you were implicitly invoking that moregeneral context.I am all for casting mathematical concepts into set theory terms,like functions being viewed as subset of cartesian product ofdomain and range. But, it appears that you are trying to castevery mathematical statement into terms of functions. Aspointed out by other posters, category theory provides a generalcontext where ideas viewed as distinct become to be viewed asparticular cases of a more general catogorical situation.This unifying viewpoint is more important than just beingable to say that you have a functor from the class of all groupsto its identity element.-- Bill Hale = > [...] we say x < x^2, and I believe you will agree that we are> thus implicitly using the function f(x)=x^2. I don't agree that we are implicitly using the function f(x) = x^2.> Here we are at a disagreement. I am not trying to bash you or claimyou're wrong, I'm merely saying I still am not convinced. Here is myreasoning:1. If two statements are the same, then they both make use of the samethings2. The statements x < x^2 and x < f(x) are the same (whenf(x)=x^2)3. Clearly, the second statement above uses f(x)4. Therefor, by 1), 2), and 3), we conclude that the statement x 1. If two statements are the same, then they both make use of the>same thingsWhat do you mean by the same? If you really mean that they are thesame, then your next statement is false.>2. The statements x < x^2 and x < f(x) are the same (when>f(x)=x^2)Only if you are using a different meaning of the same from the onein 1. above.>Now I am not trying to be stubborn, it's just that I am the type of>person who urgently needs to understand things. Try reading the responses you already got.>Clearly a de'nition like h(x)=h(x) is circular. Don't confuse a de'nition with a theorem.>the replacement axiomApplies to theorems.>This is very weird, Yes. The Devil is in the details, and you need to start payingattention to the details or you will keep getting wierd results.-- Shmuel (Seymour J.) Metz, SysProg and JOATnot reply to => 1. If two statements are the same, then they both make use of the same> things.I have no idea what it means for a statement to make use of a thing. =>> [...] we say x < x^2, and I believe you will agree that we are>> thus implicitly using the function f(x)=x^2.>> I don't agree that we are implicitly using the function f(x) = x^2.> Here we are at a disagreement. I am not trying to bash you or claim> you're wrong, I'm merely saying I still am not convinced. Here is my> reasoning:> 1. If two statements are the same, then they both make use of the same> things> 2. The statements x < x^2 and x < f(x) are the same (when> f(x)=x^2)This is wrong. The statements are not the same, because only one of themmentions a function f.> 3. Clearly, the second statement above uses f(x)> 4. Therefor, by 1), 2), and 3), we conclude that the statement x <> x^2> makes use of f(x).No, it's exactly the other way around. It's the de'nition of thefunction f that makes implicit use of the multiplication operation on thereals.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. => 2. The statements x < x^2 and x < f(x) are the same (when> f(x)=x^2) This is wrong. The statements are not the same, because only one of them> mentions a function f.> Let P(x) denote the logic statement x < x^2Let Q(x) denote the logic statement x < f(x)P and Q are unequal iff there is some real x such that P(x) != Q(x)Else, they are equalIt seems to me upon inspection (though I keep an open mind tocorrection since I am but an amateur) that P and Q are equal- in thesense that for any x, P(x)=Q(x).And since they are equal, if one has a given property, the other mustas well. The property employs the function f(x)=x^2 is possessed byQ, and therefor by P as well.Where am I erring?This is all quite confusing, and I fear I am outwearing my welcome atsci.math by pushing this issue so stubbornly, so I beg that youforgive me and know that I am just a naive person who humbly desiresto understand these things.Sniz Pilbor tanbanso@iinet.net.auX-CompuServe-Customer: YesX-Coriate: admin@interspeed.co.nzX-Ecrate: tanandtanlawyers.comX-Punge: Micro$oft said:>if one has a given property, What do you mean by has a given property? Your usage seems totranscend the values of the propositional functions, in which case twopropositional functions with the same values need not have the sameproperties.-- Shmuel (Seymour J.) Metz, SysProg and tb@becket.becket.net => Let P(x) denote the logic statement x < x^2> Let Q(x) denote the logic statement x < f(x) P and Q are unequal iff there is some real x such that P(x) != Q(x)> Else, they are equalThey are not equal, because sentences are not extensional. Differentsentences can be logically equivalent, and yet they are stilldifferent sentences.For example:George W. Bush is president.The eldest son of George H. W. Bush is president.are logically equivalent in any world in which GWB is the eldest sonof GHWB (such as, for example, the real world). But they are hardlyequal sentences which share all properties. For example, the 'rstone has twenty-two letters and two periods; the second hasthirty-seven letters and three periods.Also, the 'rst does not mention GHWB, but the second does.Thomas =>> 2. The statements x < x^2 and x < f(x) are the same (when>> f(x)=x^2)>> This is wrong. The statements are not the same, because only one of them>> mentions a function f.> Let P(x) denote the logic statement x < x^2> Let Q(x) denote the logic statement x < f(x)> P and Q are unequal iff there is some real x such that P(x) != Q(x)> Else, they are equalThe statements are logically equivalent, but they are not the same statement.> It seems to me upon inspection (though I keep an open mind to> correction since I am but an amateur) that P and Q are equal- in the> sense that for any x, P(x)=Q(x).> And since they are equal, if one has a given property, the other must> as well. The property employs the function f(x)=x^2 is possessed by> Q, and therefor by P as well.> Where am I erring?The following statements are logically equivalent when applied to the naturalnumbers, but they are not equal: 1. P(x) =def x is prime. 2. Q(x) =def x > 1 and x is not composite.P(x) employs 8 letters. Therefore, Q(x) must employ 8 letters as well.> This is all quite confusing, and I fear I am outwearing my welcome at> sci.math by pushing this issue so stubbornly, so I beg that you> forgive me and know that I am just a naive person who humbly desires> to understand these things.-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. =>In my previous thread, there seemed to be a general lack of consensus>with regard to whether algebraists implicitly invoke a functor when>they say If G is a group, let G_e be its identityNo, there was no lack of consensus. Most of us simply did not addressthe claim and simply went on to say how one could de'ne such a'function'. But the fact is, there is no need to have a functionwhose domain is all groups before you can start talking about theidentity of a given group.There are many ways of describing a group; it can be a set G with abinary operation * which satis'es certain axioms, in which case thefact that G satis'es the axioms automatically gives you anidentity. A more obvious way is to say it is a set G, with threeoperations; a binary operation *, a unary operation ^{-1}, and anullary operation e, which satis'es certain identities. The groupitself already comes equipped with a way of identitfying its identity:the nullary operation e.In fact, that is all you need: for every group G, a nullary operationG->G whose image is the identity. Then you are not invoking a generalfunction whose arguments are any group, and whose response is theidentity of the group. You are invoking a very speci'c function,associated to the group G itself, which gives you the identity of G.The existence of such a function is guaranteed by the very propertiesthat de'ne a group.Or there are other ways in which one can de'ne a function that hasthe properties you described. Though such a function is not NEEDED todo group theory.>More generally, if something is de'ned in such a way that it must>possess something else (as, for instance, a group having to have an>identity, by the very de'nition of a group), it seems to me that that>does not mean we are no longer using a hidden function/functor when we>call up that something else.Nor does it mean we ->ARE<-. And certainly, it does ->not<- mean weMUST have a function whose domain is all such somethings and whosecodomain is all things that they possess. All you need is for eachsomething G, a function whose domain is G^{0} = {emptyset}, and whosecodomain is the singleton consisting of the something else itpossesses. In the example you mentioned, given a group G, let e be itsidentity. You do not need to invoke a function de'ned for ALL groups:you may simply invoke a function whose domain is {emptyset} and whosecodomain is {e}. You don't care about any other groups besides the onethat show up in your argument. == ==It's not denial. I'm just very selective about what I accept as reality. --- Calvin (Calvin and Hobbes) tb@becket.becket.net => In my previous thread, there seemed to be a general lack of consensus> with regard to whether algebraists implicitly invoke a functor when> they say If G is a group, let G_e be its identityThere was no lack of consensus. Everyone agreed that algebraists donot need such a function, nor do they invoke it.The discussion was about the different question of whether such afunction is possible, which is a question of which particular settheory you are using, and whether your set theory allows functionswith domains or ranges that are proper classes.> How, then, is it any different to say,> Let G be a group. Then G's identity is in G> Here the culprit is the phrase G's identity. The way I see it, this> is the same as using a functor implicitly, just like its' [x's]> square.The phrase Let G be a group is really an abbreviation for:Let G = be a group. (Where you've decided that the orderis set, operation, identity.Thomas =In the Pfaf'andU = A_1.dx_1 + A_2.dx_2 + ...+A_n.dx_nif A_1, A_2,...are twice continuously differentiable _functions_ ofthe variables x_1, x_2,...etc. then a necessary condition for theintegrability of dU is the equality of the partial derviatives@A_i/@dx_k = @A_k/@x_iand there is also a much longer expression involving any three of theA's that will give the suf'cient condition for the existence of anintegrating factor.My question is, what if the A_i are not simply functions of x_k butrather functionals? Say, for exmaple, A_1 depends explicitly on (x_1 *x_2), or (h*x_1), where * denotes the convolution operator and h(t) isa given function, what can then guarantee the integrability of dU? =|> If A is a nonsingular 3 x 3 matrix with nonnegative entries, then why must A|> have a positive real eigenvalue?|> ...The characteristic equation (setting the determinant with the eigenvaluesubtracted from the diagonal to zero) is equivalent to 'nding the rootsof a cubic polynomial; so it's clear that there must be a real eigenvalue.Writing down the de'nition of the eigenvalue as A*v = lambda *vfor an eigenvector v and playing around with the signs it is alsoclear that lambda must stay positive (at least if all threeCartesian components of v are positive or negative... which is effectivleythe same as eigenvectors are only de'ned up to a const...) => If A is a nonsingular 3 x 3 matrix with nonnegative entries, then why>> must A have a positive real eigenvalue?>> Mike This is not true. For example 1 0 0> 0 0 1> 0 1 0 has eigenvalues 1,So, 1 is no longer positive ?> 1, and -1. To the OP: this is (part of) the Perron-Frobenius theorem.-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) = Howdy everybody, I'm reading Peskin and Schroeder's Intro to QFT and in this> book the author constantly refers to c-numbers... without> saying what a c-number is. I couldn't 'nd c-number> on mathworld.wolfram.com or physicsworld.wolfram.com. Can someone please tell me what the hell a c-number is?Adding yet another interpretation besides commuting and classical: Ithink they mean a complex number (which obviously is both commuting andclassical).I think they de'ned it in this way somewhere in their book, butscanning the 'rst few pages, I can't 'nd it... :-(Bye,Bjoern# = Forbidden archeology by Cremo, Thompson! Like the name says: Forbidden I urge you not to read it!You might try reading instead.Bye,Bjoern =>Let's be serious for once.>>Consider an object being accelerated by a idealistic jet of water or a>continuous Ostream of elastic ping pong balls'. What is its subsequent velocity>pattern?>>accelerated beyond the operating speed of the accelerating 'elds, ie at Oc'. I>hope it might also produce a relationship that is equivalent to mass>'appearing' to increase with velocity by gamma.)>Please de'ne what you mean by the operating speed of an>>accelerating 'eld. I've been in physics research for over 20>>years, and I've never heard that term.>>Do you mean phase velocity, group velocity, how fast the>>operators turn the knobs, what?>>I think you forgot to answer the question, Henry.>Why is that?>> yes, for some strange reason I Oforget' to answer anything EjP asks.Considering that he asked you about the meaningof a meaningless statement, I don't 'nd the reason strange at all.Paul, not puzzledExpires: 28 days =>accelerated beyond the operating speed of the accelerating 'elds, ie at Oc'. I>>hope it might also produce a relationship that is equivalent to mass>>'appearing' to increase with velocity by gamma.)>>Please de'ne what you mean by the operating speed of an>accelerating 'eld. I've been in physics research for over 20>years, and I've never heard that term.>Do you mean phase velocity, group velocity, how fast the>operators turn the knobs, what?>>I think you forgot to answer the question, Henry.>>Why is that?>> yes, for some strange reason I Oforget' to answer anything EjP asks.>>Considering that he asked you about the meaning>of a meaningless statement, I don't 'nd the reason strange at all.>>Paul, not puzzled>Paul, is your memory failing?I explained this to you last year. If 'elds acted instantaneously, we would beable to use them for instantaneous comunication.Do you really want that?Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>> accelerated beyond the operating speed of the accelerating 'elds, ie at Oc'. I>>hope it might also produce a relationship that is equivalent to mass>>'appearing' to increase with velocity by gamma.)>Please de'ne what you mean by the operating speed of an>accelerating 'eld. I've been in physics research for over 20>years, and I've never heard that term.>Do you mean phase velocity, group velocity, how fast the>operators turn the knobs, what?>>I think you forgot to answer the question, Henry.>>Why is that?>> yes, for some strange reason I Oforget' to answer anything EjP asks.>>Considering that he asked you about the meaning>of a meaningless statement, I don't 'nd the reason strange at all.>>Paul, not puzzled> Paul, is your memory failing?>> I explained this to you last year.Henry, is your memory failing?Because this year, your aswer was: No I cannot explain.> If 'elds acted instantaneously, we would be> able to use them for instantaneous communication.Please explain how you can use the fact that a force isa static electric 'eld, for instantaneous communication.Paul, puzzledExpires: 28 days =>>I think you forgot to answer the question, Henry.>Why is that?>>yes, for some strange reason I Oforget' to answer anything EjP asks.>>Considering that he asked you about the meaning>>of a meaningless statement, I don't 'nd the reason strange at all.>>Paul, not puzzled>> Paul, is your memory failing?>> I explained this to you last year.>>Henry, is your memory failing?>Because this year, your aswer was:> No I cannot explain.> If 'elds acted instantaneously, we would be>> able to use them for instantaneous communication.>>Please explain how you can use the fact that a force is>a static electric 'eld, for instantaneous communication.>>Paul, puzzled>I'm sure some bright QMian would 'nd a way.Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>I understand very well why you are desperate to divert>the attention from the fact that you know very well that>the SR prediction I showed above is experimentally veri'ed>in accelerators all over the world all the time, while>the Newtonian prediction is falsi'ed all the time.>> Your idea of the ONewtonian prediction' is just a diversion... from the fact that the prediction of NM fails by ordersof magnitude while the prediction of SR is correct?> Read what I said to Randy. That is the real reason why mass appears to increase> and the required energy shoots up enormously as c is approached.And Henry knows the REAL reason is: As the electron approaches the speed at which the 'eld acts, back radiation from the electron Oneutralizes' a volume around itself. The 'eld in its vicinity is more or less reversed by the electron's own movement. This requires a great deal of energy; one single charge creating a Olittle neutral sphere' in a strong 'eld. This energy also shows up in bolometer experiments.Paul, dazzled =>I understand very well why you are desperate to divert>the attention from the fact that you know very well that>the SR prediction I showed above is experimentally veri'ed>in accelerators all over the world all the time, while>the Newtonian prediction is falsi'ed all the time.>> Your idea of the ONewtonian prediction' is just a diversion. .. from the fact that the prediction of NM fails by orders> of magnitude while the prediction of SR is correct? Read what I said to Randy. That is the real reason why mass appears to increase> and the required energy shoots up enormously as c is approached. And Henry knows the REAL reason is:> As the electron approaches the speed at which the 'eld acts,> back radiation from the electron Oneutralizes' a volume around itself.> The 'eld in its vicinity is more or less reversed by the electron's own> movement. This requires a great deal of energy; one single charge creating a> Olittle neutral sphere' in a strong 'eld. This energy also shows up in> bolometer experiments.> I missed this explanation. Having read it, I can't makeheads or tails of it.Henry: Does whatever you are trying to describe have anequivalent in the ping-pong model? If I am trying todrive a vehicle by throwing 100 m/sec ping-pong ballsat it, so it has a limiting velocity of 100 m/sec,will the kinetic energy continue to rise beyond0.5*m*100^2 and the momentum continue to rise beyondm*100 due to some sort of back 'eld?If not, what do electrons have that a ping-pong-balldriven vehicle does not? - RandyExpires: 28 days =>>I understand very well why you are desperate to divert>>the attention from the fact that you know very well that>>the SR prediction I showed above is experimentally veri'ed>>in accelerators all over the world all the time, while>>the Newtonian prediction is falsi'ed all the time.>> Your idea of the ONewtonian prediction' is just a diversion.>> .. from the fact that the prediction of NM fails by orders>> of magnitude while the prediction of SR is correct?>> Read what I said to Randy. That is the real reason why mass appears to increase>> and the required energy shoots up enormously as c is approached.>> And Henry knows the REAL reason is:>> As the electron approaches the speed at which the 'eld acts,>> back radiation from the electron Oneutralizes' a volume around itself.>> The 'eld in its vicinity is more or less reversed by the electron's own>> movement. This requires a great deal of energy; one single charge creating a>> Olittle neutral sphere' in a strong 'eld. This energy also shows up in>> bolometer experiments.>>I missed this explanation. Having read it, I can't make>heads or tails of it.>>Henry: Does whatever you are trying to describe have an>equivalent in the ping-pong model? If I am trying to>drive a vehicle by throwing 100 m/sec ping-pong balls>at it, so it has a limiting velocity of 100 m/sec,>will the kinetic energy continue to rise beyond>0.5*m*100^2 and the momentum continue to rise beyond>m*100 due to some sort of back 'eld?>>If not, what do electrons have that a ping-pong-ball>driven vehicle does not?>> - RandyMass of dimension 2.Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htmExpires: 28 days =>I understand very well why you are desperate to divert>>the attention from the fact that you know very well that>>the SR prediction I showed above is experimentally veri'ed>>in accelerators all over the world all the time, while>>the Newtonian prediction is falsi'ed all the time.>> Your idea of the ONewtonian prediction' is just a diversion.>>.. from the fact that the prediction of NM fails by orders>of magnitude while the prediction of SR is correct?> Read what I said to Randy. That is the real reason why mass appears to increase>> and the required energy shoots up enormously as c is approached.>>And Henry knows the REAL reason is:> As the electron approaches the speed at which the 'eld acts,> back radiation from the electron Oneutralizes' a volume around itself.> The 'eld in its vicinity is more or less reversed by the electron's own> movement. This requires a great deal of energy; one single charge creating a> Olittle neutral sphere' in a strong 'eld. This energy also shows up in> bolometer experiments.>That's OK Paul. A physical explanation is worth a thousand meaningless mathsequations.>>Paul, dazzled...by the novelty.....>Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>>And they claim a simple Omass increase'.>>No they don't. If you actually read this newsgroup, you'd>>know that the term mass is used by most physicists to>>to refer to an invariant quantity.>>The term used is Orelativistic mass increase'.If you actually read this newsgroup, you'd know that the termrelativistic mass is no longer favored, and that most physiciststhese days prefer to reserve the term mass to refer to an invariantquantity. Where m used to appear in some formulas (such as E =mc^2), gamma*m is now used. - RandyExpires: 28 days => Henri Wilson.>> See why relativity is wrong:>> http://www.users.bigpond.com/HeWn/index.htm>>It would be nice if you used more text and fewer programs. I'm not >explanation appears to be contained in them, your website says nothing >that I am willing to look at.All my programs have been discussed at length on the NG. I gather you are newehere.Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>It would be nice if you used more text and fewer programs. I'm not>explanation appears to be contained in them, your website says nothing>that I am willing to look at.If the speed of light is a universal constant in all frames of reference,and in a certain situation light takes a longer path when seen from oneperspective than it does from another, then it must take a longer time fromthat perspective than it does from the other.Or - the longer path takes the longer time.Usually, the relativist will say something like...The beam moves vertically in the moving frame, but this is seen as adiagonal line in the stationary frame.|| | | Therefore time in the moving frame is less than time in the stationaryframe, taa-daaaa!, I'm so clever, I understand relativity, mom!Then he does some elementary algebra which I won't bore you with, and walksoff, con'dent he's right.Trouble is, if we bend the light beam through the angle arctan(v/c) in themoving frame, this is what happens.t0.........* at1........t1.........* bt2......t2........t2.........* ct3..t3.....t3.......t3.........* dThe moving source has moved left as time passed, but the ray is vertical inthe stationary frame. The tip of the ray, *, remains the same distance fromthe edge of the page, at a,b,c,and d, but the source has moved to the left.So, applying our rule that the longer path takes the longer time, the longertime is in the moving frame, not the stationary frame, contrary to therelativists claim that he understands anything at all.At this point the relativist will start to splutter about unsynchronizedclocks.(Did I mention any clocks until now? No, of course not.)He will claim that in the stationary frame two clocks are separated|S| | | A Bby a distance vt, and work this into his argument.(Oh no he won't, you cry!)Oh yes he will, I've seen it done.Now, of course it is true that the distance S-A-B is greater than thedistance S-A, so he has found a trick up his sleeve to make time less in themoving frame once more. What a clever relativist!But......... that isn't the path the light takes. It doesn't go from S to A and A to B,bending through a right-angle. It takes the short-cut, direct from S to B.The frame with the longer path has the longer time. Moving clocks speed up,and all because I tilted the §ashlight. Ergo, Einstein's relativity isstupidity, and relativists are gullible fools.(To Henri: No special math needed, old chap. Keep it simple :-)AndroclesExpires: 28 days =>It would be nice if you used more text and fewer programs. I'm not>>explanation appears to be contained in them, your website says nothing>>that I am willing to look at.>>If the speed of light is a universal constant in all frames of reference,>and in a certain situation light takes a longer path when seen from one>perspective than it does from another, then it must take a longer time from>that perspective than it does from the other.>Or - the longer path takes the longer time.>>Usually, the relativist will say something like...>>The beam moves vertically in the moving frame, but this is seen as a>diagonal line in the stationary frame.>|>| >Therefore time in the moving frame is less than time in the stationary>frame, taa-daaaa!, I'm so clever, I understand relativity, mom!>Then he does some elementary algebra which I won't bore you with, and walks>off, con'dent he's right.Yes. All relativists seem to suffer from the same Ospatial-ability de'ciencysyndrome'.As I have pointed out many times, a vertical beam appears vertical in allframes. (http://www.users.bigpond.com/hewn/movingframe.exe) Each in'nitesimalelement of the vertical beam follows its own unique diagonal path in the movingframe. There is no conceiveable reason to believe that such an astractconstruct constitutes light, traveling at c. My demo shows that such an elementcannot be the same as one belonging to a laser beam deliberately aimeddiagonally in the moving frame. Raindrops take the same time to reach the ground even though they appear to bemoving diagonally through the window of your moving car.>>Trouble is, if we bend the light beam through the angle arctan(v/c) in the>moving frame, this is what happens.>t0.........* a>>t1........>t1.........* b>>t2......>t2........>t2.........* c>>t3..>t3.....>t3.......>t3.........* d>The moving source has moved left as time passed, but the ray is vertical in>the stationary frame. The tip of the ray, *, remains the same distance from>the edge of the page, at a,b,c,and d, but the source has moved to the left.>So, applying our rule that the longer path takes the longer time, the longer>time is in the moving frame, not the stationary frame, contrary to the>relativists claim that he understands anything at all.>At this point the relativist will start to splutter about unsynchronized>clocks.>(Did I mention any clocks until now? No, of course not.)>He will claim that in the stationary frame two clocks are separated>|S>| >A B>by a distance vt, and work this into his argument.>(Oh no he won't, you cry!)>Oh yes he will, I've seen it done.>Now, of course it is true that the distance S-A-B is greater than the>distance S-A, so he has found a trick up his sleeve to make time less in the>moving frame once more. What a clever relativist!>>But....>.>.>.>.>.> that isn't the path the light takes. It doesn't go from S to A and A to B,>bending through a right-angle. It takes the short-cut, direct from S to B.>The frame with the longer path has the longer time. Moving clocks speed up,>and all because I tilted the §ashlight. Ergo, Einstein's relativity is>stupidity, and relativists are gullible fools.Very true.>(To Henri: No special math needed, old chap. Keep it simple :-) Nothing can show this more simply than my demo.However, clocks can appear to run either slow or fast depending on whether theyare receding or approaching.In reality, they don't PHYSICALLY change at all with movement.The term Ogamma' is wrong. It cannot contain Ov^2'. >Androcles>Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>>It would be nice if you used more text and fewer programs. I'm not>>explanation appears to be contained in them, your website says nothing>>that I am willing to look at.>>If the speed of light is a universal constant in all frames of reference,>and in a certain situation light takes a longer path when seen from one>perspective than it does from another, then it must take a longer timefrom>that perspective than it does from the other.>Or - the longer path takes the longer time.>>Usually, the relativist will say something like...>>The beam moves vertically in the moving frame, but this is seen as a>diagonal line in the stationary frame.>|>| >Therefore time in the moving frame is less than time in the stationary>frame, taa-daaaa!, I'm so clever, I understand relativity, mom!>Then he does some elementary algebra which I won't bore you with, andwalks>off, con'dent he's right.>> Yes. All relativists seem to suffer from the same Ospatial-abilityde'ciency> syndrome'.> As I have pointed out many times, a vertical beam appears vertical in all> frames. (http://www.users.bigpond.com/hewn/movingframe.exe) Eachin'nitesimal> element of the vertical beam follows its own unique diagonal path in themoving> frame. There is no conceiveable reason to believe that such an astract> construct constitutes light, traveling at c. My demo shows that such anelement> cannot be the same as one belonging to a laser beam deliberately aimed> diagonally in the moving frame.>> Raindrops take the same time to reach the ground even though they appearto be> moving diagonally through the window of your moving car.>Trouble is, if we bend the light beam through the angle arctan(v/c) inthe>moving frame, this is what happens.>t0.........* a>>t1........>t1.........* b>>t2......>t2........>t2.........* c>>t3..>t3.....>t3.......>t3.........* d>The moving source has moved left as time passed, but the ray is verticalin>the stationary frame. The tip of the ray, *, remains the same distancefrom>the edge of the page, at a,b,c,and d, but the source has moved to theleft.>So, applying our rule that the longer path takes the longer time, thelonger>time is in the moving frame, not the stationary frame, contrary to the>relativists claim that he understands anything at all.>At this point the relativist will start to splutter about unsynchronized>clocks.>(Did I mention any clocks until now? No, of course not.)>He will claim that in the stationary frame two clocks are separated>|S>| >A B>by a distance vt, and work this into his argument.>(Oh no he won't, you cry!)>Oh yes he will, I've seen it done.>Now, of course it is true that the distance S-A-B is greater than the>distance S-A, so he has found a trick up his sleeve to make time less inthe>moving frame once more. What a clever relativist!>>But....>.>.>.>.>.> that isn't the path the light takes. It doesn't go from S to A and A toB,>bending through a right-angle. It takes the short-cut, direct from S toB.>The frame with the longer path has the longer time. Moving clocks speedup,>and all because I tilted the §ashlight. Ergo, Einstein's relativity is>stupidity, and relativists are gullible fools.>> Very true.>>(To Henri: No special math needed, old chap. Keep it simple :-)>> Nothing can show this more simply than my demo.>> However, clocks can appear to run either slow or fast depending on whetherthey> are receding or approaching.Of course. Doppler shift.> In reality, they don't PHYSICALLY change at all with movement.Quite right.> The term Ogamma' is wrong. It cannot contain Ov^2'.Err...The distance the light moves from S to A is ct.The distance from A to B is vt.The distance from S to B is sqrt([ct]^2 +[vt]^2) by Pythagoras.We can choose an arbitrary unit of time for t, and make t = 1S to B = hypotenuse = sqrt(c^2 +v^2)AndroclesExpires: 28 days => However, clocks can appear to run either slow or fast depending on whether>they>> are receding or approaching.>Of course. Doppler shift.> In reality, they don't PHYSICALLY change at all with movement.>Quite right.>> The term Ogamma' is wrong. It cannot contain Ov^2'.>Err...>The distance the light moves from S to A is ct.>The distance from A to B is vt.>The distance from S to B is sqrt([ct]^2 +[vt]^2) by Pythagoras.>We can choose an arbitrary unit of time for t, and make t = 1>S to B = hypotenuse = sqrt(c^2 +v^2)>Androcles>What moves diagonally is not light.The diagonal is just a line representing the path of an in'nitesimally smallelement of the light beam. The beam itself remains vertical but appears to movesideways in the moving observer's frame. The vertical component of eachelement's velocity is not affected by observer movement. How could it be?So Yes, each in'nitesimal element moves at sqrt(c^2+v^2) along it owndiagonal. It is the only element that moves along that diagonal. Thereforethere is no diagonal light beam moving at c. Therefore SR is the greatest loadof codswallop ever dumped on the human race.Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm => So Yes, each in'nitesimal element moves at sqrt(c^2+v^2) along it own> diagonal. It is the only element that moves along that diagonal. Therefore> there is no diagonal light beam moving at c. Therefore SR is the greatestload> of codswallop ever dumped on the human race.Whoa... ease up, there, H! If I'm §ying a microlite at 100mph across atennis court (along the net) just as a 100mph ace is served straight downthe middle, the ball takes a diagonal path in *my frame of reference*. Theonly silly part would be if I insisted the ball's speed was 100mph insteadof 141mph.The light certainly does move diagonally. Of course, if my clock sloweddown, it would appear to move even faster, and that's the codswallop :)AndroclesExpires: 28 days => So Yes, each in'nitesimal element moves at sqrt(c^2+v^2) along it own>> diagonal. It is the only element that moves along that diagonal. Therefore>> there is no diagonal light beam moving at c. Therefore SR is the greatest>load>> of codswallop ever dumped on the human race.>>Whoa... ease up, there, H! If I'm §ying a microlite at 100mph across a>tennis court (along the net) just as a 100mph ace is served straight down>the middle, the ball takes a diagonal path in *my frame of reference*. The>only silly part would be if I insisted the ball's speed was 100mph instead>of 141mph.But if a stream of balls was 'red from a machine gun along that same line, thestream would always remain aligned vertically in your frame. Each ball wouldmove along its own diagonal path at sqrt(c^2+v^2). Take that to the limit by decreasing ball size and increasing frequency and youhave the Olight ray equivalent'. And, of course, each ball takes the same time to reach its target irrespectiveof your speed. No nonsense about clocks changing rates.>The light certainly does move diagonally. Of course, if my clock slowed>down, it would appear to move even faster, and that's the codswallop :)>Androcles>Sure is! Clock rates are not physically dependent on velocity. My demo Omovingrame.exe' well illustrates this monumental blunder made byEinstein et al. It takes only a few seconds to run. See also: Overtical.exe'It is quite obvious that a diagonally aimed laser beam in the rest observerframe is NOT identical to an apparently diagonally moving element of a verticallight ray that moves sideways acros that frame.How could SRians be so plainly stoopid?Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm =>> So Yes, each in'nitesimal element moves at sqrt(c^2+v^2) along it own>> diagonal. It is the only element that moves along that diagonal.Therefore>> there is no diagonal light beam moving at c. Therefore SR is thegreatest>load>> of codswallop ever dumped on the human race.>>Whoa... ease up, there, H! If I'm §ying a microlite at 100mph across a>tennis court (along the net) just as a 100mph ace is served straight down>the middle, the ball takes a diagonal path in *my frame of reference*.The>only silly part would be if I insisted the ball's speed was 100mphinstead>of 141mph.>> But if a stream of balls was 'red from a machine gun along that sameline, the> stream would always remain aligned vertically in your frame. Each ballwould> move along its own diagonal path at sqrt(c^2+v^2).>> Take that to the limit by decreasing ball size and increasing frequencyand you> have the Olight ray equivalent'.>> And, of course, each ball takes the same time to reach its targetirrespective> of your speed. No nonsense about clocks changing rates.>The light certainly does move diagonally. Of course, if my clock slowed>down, it would appear to move even faster, and that's the codswallop :)>Androcles> Sure is! Clock rates are not physically dependent on velocity.>> My demo Omovingrame.exe' well illustrates this monumental blunder made by> Einstein et al. It takes only a few seconds to run. See also:'vertical.exe'>> It is quite obvious that a diagonally aimed laser beam in the restobserver> frame is NOT identical to an apparently diagonally moving element of avertical> light ray that moves sideways acros that frame.>> How could SRians be so plainly stoopid?>> Henri Wilson.Beats me. I think they get convinced and then there's no going back. But Iwill tell you something. The debates on this newsgroup used to beaetherialists against relativists. The aetherialists are losing ground, andemission theory is gaining. Young people are now more convinced that everbefore that the speed of light is source dependent as their intuition tellsthem, and not aether dependent. As time passes relativity will fall intodisrepute, and the younger ones will investigate a whole new physics, rebornout of Newton. They'll build accelerators for EM radiation that will vastlyimprove interplanetary communication, and someday FTL probes to investigatedistant stars and their planets. Other facets, unimaginable to us now, willcome out of it. This I predict.Glad to have you aboard. Keep the focus on the newbies, and treat them withlogic. It does no good 'ghting the diehards, although I'll agree it can befun.AndroclesExpires: 28 days =>>So Yes, each in'nitesimal element moves at sqrt(c^2+v^2) along it own>diagonal. It is the only element that moves along that diagonal.>Therefore>there is no diagonal light beam moving at c. Therefore SR is the>greatest>>load>of codswallop ever dumped on the human race.>>Whoa... ease up, there, H! If I'm §ying a microlite at 100mph across a>>tennis court (along the net) just as a 100mph ace is served straight down>>the middle, the ball takes a diagonal path in *my frame of reference*.>The>>only silly part would be if I insisted the ball's speed was 100mph>instead>>of 141mph.>> But if a stream of balls was 'red from a machine gun along that same>line, the>> stream would always remain aligned vertically in your frame. Each ball>would>> move along its own diagonal path at sqrt(c^2+v^2).>> Take that to the limit by decreasing ball size and increasing frequency>and you>> have the Olight ray equivalent'.>> And, of course, each ball takes the same time to reach its target>irrespective>> of your speed. No nonsense about clocks changing rates.>>The light certainly does move diagonally. Of course, if my clock slowed>>down, it would appear to move even faster, and that's the codswallop :)>>Androcles>> Sure is! Clock rates are not physically dependent on velocity.>> My demo Omovingrame.exe' well illustrates this monumental blunder made by>> Einstein et al. It takes only a few seconds to run. See also:>'vertical.exe'>> It is quite obvious that a diagonally aimed laser beam in the rest>observer>> frame is NOT identical to an apparently diagonally moving element of a>vertical>> light ray that moves sideways acros that frame.>> How could SRians be so plainly stoopid?>> Henri Wilson.>Beats me. I think they get convinced and then there's no going back. But I>will tell you something. The debates on this newsgroup used to be>aetherialists against relativists. The aetherialists are losing ground, and>emission theory is gaining. Young people are now more convinced that ever>before that the speed of light is source dependent as their intuition tells>them, and not aether dependent. As time passes relativity will fall into>disrepute, and the younger ones will investigate a whole new physics, reborn>out of Newton. They'll build accelerators for EM radiation that will vastly>improve interplanetary communication, and someday FTL probes to investigate>distant stars and their planets. Other facets, unimaginable to us now, will>come out of it. This I predict.>Glad to have you aboard. Keep the focus on the newbies, and treat them with>logic. It does no good 'ghting the diehards, although I'll agree it can be>fun.>Androcles>I think there is more to source dependency than has hitherto been considered.There must be other factors involved because De Sitter was basically correct.(I know you will disagree) There is no doubt that many binary pairs shouldappear differently if straight c+v is correct.As you know, my H-aether theory attempts to provide ONE explanation. Lightalways leaves a source at c but changes speed as it travels, due to bothgravity gradients and weak interaction with other EM. This seems the only way to explain how all photons can travel through space ata (nearly) common velocity. Relativity certainly provides no solution to this,even though know-alls like Dick the Fumble would like to believe it does. In the case of binary pairs, is there a chance that light speed from each issomehow in§uenced by other factors. For instance, might the centre of gravityof the pair somehw enter the picture? Henri Wilson.See why relativity is wrong:http://www.users.bigpond.com/HeWn/index.htm Glad to have you aboard. Keep the focus on the newbies, and treat them with> logic.A 'ne pair http://users.pandora.be/vdmoortel/dirk/Physics/Fumbles/ AndersenLogic.html http://users.pandora.be/vdmoortel/dirk/Physics/Fumbles/ LogicBull.html http://users.pandora.be/vdmoortel/dirk/Physics/Fumbles/ Gibberish.html http://users.pandora.be/vdmoortel/dirk/Physics/Fumbles/ Cornered.htmlDirk Vdm =Suppose x1,x2,...,xn is a random permutation of 1,...,n.Now sweep through x1,x2,...,xn left-to-right, looking for 1,...,n in increasing order. Let m be the greatest value found in the sweep. If m < n, sweep again, looking for m+1,...,n. Repeat until n is found.Example:Sweep 864513729----- --------- 1 1 2 2 3 3 45 4 6 7 5 8 9What is the distribution of the number of sweeps? I.e., if S is the number of sweeps, what is Pr(S=s)(s=1,...,n)? => Suppose x1,x2,...,xn is a random permutation of 1,...,n.> Now sweep through x1,x2,...,xn left-to-right, looking for > 1,...,n in increasing order. Let m be the greatest value > found in the sweep. If m < n, sweep again, looking for > m+1,...,n. Repeat until n is found. Example:> Sweep 864513729> ----- ---------> 1 1 2> 2 3> 3 45> 4 6 7> 5 8 9 What is the distribution of the number of sweeps? I.e., > if S is the number of sweeps, what is Pr(S=s)(s=1,...,n)?I am not sure, but I think this has something to do with Euleriannumbers:http://mathworld.wolfram.com/ EulerianNumber.html(Do not confuse with Euler numbers!)I do not know if the Mathworld info is correct, nor if the info wouldbe helpful anyway, but this is probably a good start to => Suppose x1,x2,...,xn is a random permutation of 1,...,n.> Now sweep through x1,x2,...,xn left-to-right, looking for > 1,...,n in increasing order. Let m be the greatest value > found in the sweep. If m < n, sweep again, looking for > m+1,...,n. Repeat until n is found. Example:> Sweep 864513729> ----- ---------> 1 1 2> 2 3> 3 45> 4 6 7> 5 8 9 What is the distribution of the number of sweeps? I.e., > if S is the number of sweeps, what is Pr(S=s)(s=1,...,n)? > I am not sure, but I think this has something to do with Eulerian> numbers: http://mathworld.wolfram.com/EulerianNumber.htmlYes! I didn't know the terminology, but it seems that my sweeps are properly called permutation runs:http://mathworld.wolfram.com/ PermutationRun.htmlApparently, P(S=k) = A(n,k)/n! (k=1..n)where the A(n,k) are Eulerian numbers given byA(n,1) = A(n,n) = 1A(n,k) = (n-k+1) A(n-1,k-1) + k A(n-1,k), k=2,...,n-1.r.e.s. =>Suppose x1,x2,...,xn is a random permutation of 1,...,n.>Now sweep through x1,x2,...,xn left-to-right, looking for >1,...,n in increasing order. Let m be the greatest value >found in the sweep. If m < n, sweep again, looking for >m+1,...,n. Repeat until n is found.>Example:>Sweep 864513729>----- ---------> 1 1 2> 2 3> 3 45> 4 6 7> 5 8 9>What is the distribution of the number of sweeps? I.e., >if S is the number of sweeps, what is Pr(S=s)(s=1,...,n)?I have not been able to get a complete solution of theproblem. However, there are partial results.The distribution is symmetric. That is, since a permutationand its reverse have their number of sweeps adding up ton+1, P(S=s) = P(S = n+1-s).For the following, observe that we do not need that thex's be the integers, but any n ordered objects will do,and a sweep still consists of the number of consecutiveobjects, starting from the smallest. So let G_n(t) bethe generating function of the sweeps from n objects,i.e., G_n(t) = sum P_n)(S=s)*t^n. If the 'rst elementof the permutation is k, the contribution to G_n is P_{n-1}(t)/n, k=1; t*P_{n-1}(t)/n, k=n; P_{k-1}(t)*P_{n-k}(t)/n, 1 < k < n.So n*P_n(t) = (1+t)*P_{n-1}(t) + sum P_{k-1}(t)*P_{n-k}(t).If we multiply this by z^{n-1} and sum, and let Q(t,z) = sum P_n(t)*z^n, we get Q' - t = (1+t)*Q + Q^2,differentiating being on z. I have not succeeded in getting the appropriate solution.The 'rst few generating functions are: 1 t 2 (t + t^2)/2! 3 (t + 4t^2 + t^3)/3! 4 (t + 11t^2 + 11t^3 + t^4)/4! 5 (t + 26t^2 + 66t^3 + 26t^4 + t^5)/5!-- This address is for information only. I do not claim that these viewsare those of the Statistics Department or of Purdue University.Herman Rubin, Department of Statistics, Purdue University =>Suppose x1,x2,...,xn is a random permutation of 1,...,n.>Now sweep through x1,x2,...,xn left-to-right, looking for >1,...,n in increasing order. Let m be the greatest value >found in the sweep. If m < n, sweep again, looking for >m+1,...,n. Repeat until n is found.Example:>Sweep 864513729>----- ---------> 1 1 2> 2 3> 3 45> 4 6 7> 5 8 9What is the distribution of the number of sweeps? I.e., >if S is the number of sweeps, what is Pr(S=s)(s=1,...,n)? I have not been able to get a complete solution of the> problem. However, there are partial results. The distribution is symmetric. That is, since a permutation> and its reverse have their number of sweeps adding up to> n+1, P(S=s) = P(S = n+1-s). For the following, observe that we do not need that the> x's be the integers, but any n ordered objects will do,> and a sweep still consists of the number of consecutive> objects, starting from the smallest. So let G_n(t) be> the generating function of the sweeps from n objects,> i.e., G_n(t) = sum P_n)(S=s)*t^n. If the 'rst element> of the permutation is k, the contribution to G_n is P_{n-1}(t)/n, k=1;> t*P_{n-1}(t)/n, k=n;> P_{k-1}(t)*P_{n-k}(t)/n, 1 < k < n. So n*P_n(t) = (1+t)*P_{n-1}(t) + sum P_{k-1}(t)*P_{n-k}(t). If we multiply this by z^{n-1} and sum, and let > Q(t,z) = sum P_n(t)*z^n, we get Q' - t = (1+t)*Q + Q^2, differentiating being on z. I have not succeeded in > getting the appropriate solution. The 'rst few generating functions are: 1 t> 2 (t + t^2)/2!> 3 (t + 4t^2 + t^3)/3!> 4 (t + 11t^2 + 11t^3 + t^4)/4!> 5 (t + 26t^2 + 66t^3 + 26t^4 + t^5)/5!This and Leroy Quet's reply make the connection to the Eulerian number triangle:11 1 1 4 1 1 11 11 11 26 66 26 1 ...http://mathworld.wolfram.com/EulerianNumber.htmlr.e.s. = How long has the relation between complex numbers and particular 2x2matrixes been known?Are there any future plans to Ophase out' complex numbers and replacethem with 2x2 matrixes which work exactly the same?(...Starblade Riven Darksquall...) => How long has the relation between complex numbers and particular 2x2> matrixes been known?As long as matrices have been studied.> Are there any future plans to Ophase out' complex numbers and replace> them with 2x2 matrixes which work exactly the same?No.-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlNeedless to say, I had the last laugh. Alan Partridge, _Bouncing Back_ (14 times) => Are there any future plans to Ophase out' complex numbers and replace> them with 2x2 matrixes which work exactly the same? No.How do you know? => Are there any future plans to Ophase out' complex numbers and replace>> them with 2x2 matrixes which work exactly the same?>> No.>>How do you know?I don't know how he knows, but your question leads to thequestion: Suppose that we had in fact replaced complex numberswith those matrices that work exactly the same. Since theywork exactly the same, how would we know that this had happened?David C. Ullrich =>Are there any future plans to Ophase out' complex numbers and replace>them with 2x2 matrixes which work exactly the same?>No.>>How do you know?> I don't know how he knows, but your question leads to the> question: Suppose that we had in fact replaced complex numbers> with those matrices that work exactly the same. Since they> work exactly the same, how would we know that this had > happened?Sounds like something out of a Steven Wright comedy routine.But the part I'm trying to 'gure out is, what are future plans, andhow do they differ from ordinary plans?-- Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. =>But the part I'm trying to 'gure out is, what are future plans, and>how do they differ from ordinary plans?--begin excerpt from a post to sci.skeptic in 1993-- In his essay on Irreversibility in _Surprises in Theoretical Physics_, We may try to analyze the problem somewhat more deeply by asking why it is that we can easily perform experiments in which initial conditions have to be speci'ed, but never any requiring terminal conditions. This is the real distinction between past and future. A little thought shows that this is connected with the fact that we can remember the past, and that we can make plans for the future, but not vice versa. It is evident that these statements are correct, but they do not follow from any known laws of physics. We could speculate that these facts have something to do with the way our brain functions, but we have no way of explaining the origin of this one-sidedness. We must not, of course, try to attribute it to some thermodynamic irreversibility in our brain cells, because this would amount to invoking the Second Law in a study aimed at understanding the origin of the Second Law, and we would have a circular argument.--end excerpt--HTH. HAND!Lee Rudolph =>Are there any future plans to Ophase out' complex numbers and replace>them with 2x2 matrixes which work exactly the same?>No.>>How do you know?> I don't know how he knows, but your question leads to the> question: Suppose that we had in fact replaced complex numbers> with those matrices that work exactly the same. Since they> work exactly the same, how would we know that this had > happened? Sounds like something out of a Steven Wright comedy routine. But the part I'm trying to 'gure out is, what are future plans, and> how do they differ from ordinary plans?What I mean is, say there are futuree plans to phase out the Englishsystem in America. We'd start by using both the English system andAmerican system. But we're certainly not going to just get rid of theEnglish system just like that. That's what I'm saying.At least, what we should recognize is that complex numbers and theirreal 2x2 matrix counterparts are identical in function, as long as weremember that when we imbed 2x2 matrixes in larger matrixes, that thetransposing in the classical system should not disturb the inner 2x2matrixes, and the conjugatation in the classical syswtem should notpurturb the position of the 2x2 matrixes but would transpose eachindividual 22 matrix, and combining a transpose with a conjugation inthe classical system is equivilent to just using a regulartranspotition of the entire matrix in the new system.Also, this means that all matrixes using trans-real numbers can bereduced to larger matrixes which use real numbers, either meaning thatreal matrixes are the only things that exist, or all types ofmatrixes, using real numbers only, using complex numbers, quaternions,et cetera, are acceptable.(...Starblade Riven Darksquall...) =>Are there any future plans to Ophase out' complex numbers and replace>them with 2x2 matrixes which work exactly the same?>No.>>How do you know?> I don't know how he knows, but your question leads to the> question: Suppose that we had in fact replaced complex numbers> with those matrices that work exactly the same. Since they> work exactly the same, how would we know that this had > happened? Sounds like something out of a Steven Wright comedy routine. But the part I'm trying to 'gure out is, what are future plans, and> how do they differ from ordinary plans? What I mean is, say there are futuree plans to phase out the English> system in America. We'd start by using both the English system and> American system. But we're certainly not going to just get rid of the> English system just like that. That's what I'm saying.> Whops! I meant the English system and the METRIC system. Also, this isjust an analogy, this isn't what I meant by future plans.(...Starblade Riven Darksquall...) matrixes) =>>Are there any future plans to Ophase out' complex numbers and replace>them with 2x2 matrixes which work exactly the same?>>No.>How do you know?>> I don't know how he knows, but your question leads to the> question: Suppose that we had in fact replaced complex numbers> with those matrices that work exactly the same. Since they> work exactly the same, how would we know that this had> happened?>> Sounds like something out of a Steven Wright comedy routine.>> But the part I'm trying to 'gure out is, what are future plans, and> how do they differ from ordinary plans? What I mean is, say there are futuree plans to phase out the English> system in America. We'd start by using both the English system and> American system. But we're certainly not going to just get rid of the> English system just like that. That's what I'm saying.lol. Americans are not smart enough to deal with complex numbers?Wilbert = >Are there any future plans to Ophase out' complex numbers and replace>them with 2x2 matrixes which work exactly the same?>No.>>How do you know?> I don't know how he knows, but your question leads to the> question: Suppose that we had in fact replaced complex numbers> with those matrices that work exactly the same. Since they> work exactly the same, how would we know that this had> happened?>> Sounds like something out of a Steven Wright comedy routine.>> But the part I'm trying to 'gure out is, what are future plans, and> how do they differ from ordinary plans? What I mean is, say there are futuree plans to phase out the English> system in America. We'd start by using both the English system and> American system. But we're certainly not going to just get rid of the> English system just like that. That's what I'm saying. lol. Americans are not smart enough to deal with complex numbers? WilbertThat's not what I'm saying.Also, can we have things such as e^(quat) or ln(quat) where quat is aquaternion? Has anybody ever 'gured out how to do this? Also, whatabout using lie algebras which work on quaternions?(...Starblade Riven Darksquall...) =>Also, can we have things such as e^(quat) or ln(quat) where quat is a>quaternion? Has anybody ever 'gured out how to do this? Exponentials, and logarithms of invertible elements, exist in any Banach algebra. Look up holomorphic functional calculus.Robert Israel israel@math.ubc.caDepartment of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 =