mm-175 === Subject: Clarication with announcement of new version Let me answer your question:>Hello ! Now, these points might have been addressed before but I would>really>appreciate some clarications in your proof :>>- In Def. 2.2, what does it mean .95we dene that each covering has at>least two>members' ? Does it simply mean that, if J has got one or no member we>do not>call it a covering ?For the sake of clarity, I declare:We shall not call what you would call a covering with one point asa covering. Thus, if you dare to argue with that argument, sayingthat a covering with one point is nonsesne, will be treated asnonsense, since there does not exist any such a thing in my proof.>>- In Def. 2.3, what is the meaning of indexing the left subscript of>J' ? That>is, what is the meaning of r_i ?That thing is for residue. >You explain that p_i is the i-th odd>prime,>but it is unclear what the subscript .95i' means on r.For detail, please refer to the new version. It relates to therestriction on the distinctness of prime moduli used.>- Same one, regarding the denition of P' as an intersection of P and>N. You appear to have dened things such that P(3,pl) is a subset of>N(3,q)_odd (since pl <= q), so why take the intersection or introduce>P' for that matter ?This is to let my mathematical induction happen. If we do notdene a universal set, then the whole thing of For every q ...becomes nonsense.>- A bit later, in the denition of A B, you appear to be>putting as conditions the equivalence of A and B simultaneously with>the existence of unpaired points of B ! Doesn't the equivalence imply>the nonexistence of such points ?Doesn't the equivalence imply the nonexistence of such points? ???a b c d e =: Ae f g i j =: BSay A is equivalent to B. With a corresponding positionwisely to e.Because they are equivalent, there exist pair of points. Did I getyour question correctly?>At this point I stopped reading. Could you please clarify or correct>any misunderstanding of mine ?Please read on. Check out Nature for Dr. Perelman. ( I would be sorryfor Dr. Perelman on making his name public, but he would be quiteinspiring to me as Paul Erdos would be to me. ) Just please try tounderstand with scrutiny. I am almost giving up publishing the result.But amazingly, Dr. Perelman has also not shown an interest ofpublishing his result. (Perhaps because of :)Hisanobu ShinyaNew version will be available inhttp://www.mathpreprints.comor my geocities website. approve@localhost) by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id sci.mathi don't know how to post without it being a response, Unit Circle, and i found images that only had 3 points in each Quadrant. why don't they show things like pi/12, 5pi/12, 7pi/12 ...23pi/12 and the point it lies on, on the unit circle. i have tofind out what the cosine of 19pi/12 for homework, but i only come up with an approximate value, not the exact one. i only ask for 8 points on the unit circle, can someone help me? === Subject: Re: limited unit circle> i have tofind out what the cosine of 19pi/12 for homework, but i > only come up with an approximate value, not the exact one. i only ask > for 8 points on the unit circle, can someone help me?Would it help you any if I were to point out that 19/12 = 15/12 + 4/12?-- Gerry Myerson (gerry@maths.mq.edi.ai) (i -> u for email) Myerson , cosine of 19pi/12 for homework, but i >> only come up with an approximate value, not the exact one. i only ask >> for 8 points on the unit circle, can someone help me?>>Would it help you any if I were to point out that >19/12 = 15/12 + 4/12>?Or as I had done, 19/12 = 16/12 + 3/12.Rob Johnson take out the trash before replying === Subject: Re: Candy Inspiration (in the news)> M & M packing: index.html I guess I am not surprised they pack better than spheres. If M&Ms had been VERY ¤at, it seems intuitively obvious they would> have packed even more efciently.> (as long they were oriented in the barrel so that neighboring oblate> spheroids were mostly positioned, on average, in somewhat the same> direction.)It seems intuitive to me too. If you imagine M&M's being arbitrarily long and thin (topological M&Ms) you can see that they approach the packing density you'd get if all the M&M's were ¤at -- namely 100%. I'd guess that spherical M&Ms are the LEAST efcient shape for packing. === Subject: Re: Candy Inspiration (in the news)shfry If M&Ms had been VERY ¤at, it seems intuitively obvious they would|> have packed even more efciently.|> (as long they were oriented in the barrel so that neighboring oblate|> spheroids were mostly positioned, on average, in somewhat the same|> direction.)||It seems intuitive to me too. If you imagine M&M's being arbitrarily |long and thin (topological M&Ms) you can see that they approach the |packing density you'd get if all the M&M's were ¤at -- namely 100%. I'd |guess that spherical M&Ms are the LEAST efcient shape for packing.I can believe they might pack better, but I don't see why. If they are allellipsoids oriented the same way, i.e. with their three corresponding axesparallel, it's impossible to get a better packing density than what youcan get for spheres, because there is a linear transformation whichtakes all of them from ellipsoids to spheres.In your argument, you have two limits being taken. One is the limit asthe shape becomes very ¤at. The other is the limit in the denition ofpacking density, namely as the volume of the box goes to innity.I don't see how you can get a packing density close to 100% for anygiven (ellipsoidal) shape, given that they are thicker in the middle andthinner at the edges. If you stacked them up like pancakes, for example,you'd still have that wasted space at the edges, plus the fact that there'sno way to ll the plane with disks without gaps.into big containers, which surely is less than the ideal best possibledensity. I can believe that M&Ms might be better at packing together insomething like the optimal spherical packing (with the linear transformationapplied to turn them into ellipsoids instead of spheres) than spheres are.It would still be interesting to know, though, whether there's any shape ofellipsoid whose *best* packing density exceeds the *best* density forspheres.Keith Ramsay === Subject: constructing realsHi all,i had this idea of dening the reals from rationals by intersectionsofsubsets of Q:Let {O_n} be a sequence of open intervals in Q s.t. |O_n| -> 0and O_n+1 is in O_n for all n.Then either U(O_n)=p/q is in Q, or U(O_n)={} in which case U(O_n)denes an irrational number.Would this be only slightly different from the approach through comments,typek === Subject: Re: constructing reals> Hi all, i had this idea of dening the reals from rationals by intersections> of> subsets of Q:> Let {O_n} be a sequence of open intervals in Q s.t. |O_n| -> 0> and O_n+1 is in O_n for all n.> Then either U(O_n)=p/q is in Q, or U(O_n)={} in which case U(O_n)> denes an irrational number.> Would this be only slightly different from the approach through the> equivalence classes of cauchy sequences ?Given such a sequence of open intervals, a suitable Cauchy sequence canbe easily constructed by interleaving the endpoints. Alternately, thesequence of lower endpoints and the sequence of upper endpoints wouldthemselves be suitable Cauchy sequences. Constructing a nested sequenceof open intervals from a Cauchy sequence is not always that easy, but Ithink it is always possible (although some of the endpoints might not beterms in the sequence).I think using intervals like this is an unneeded complication. -- Daniel W. Johnsonpanoptes@iquest.nethttp://members.iquest.net/~panoptes/ 039 53 36 N / 086 11 55 W === Subject: Re: constructing > .... > i had this idea of dening the reals from rationals by intersections> of> subsets of Q:> Let {O_n} be a sequence of open intervals in Q s.t. |O_n| -> 0> and O_n+1 is in O_n for all n.> Then either U(O_n)=p/q is in Q, or U(O_n)={} in which case U(O_n)> denes an irrational number.... See Richard Courant & Herbert Robbins, What is Mathematics? pp.68-71, General Denition of Irrational Numbers by Nested Intervals. They've got a nice diagram too. Ken Pledger. === Subject: the anticlassicalist }{ i: linguistic negation-=-=-=-=-= linguistic negation =-=-=-=-=-=-The logic of natural language has been studied by many different schools ofthought throughout history. Much of this study has pointed to many modelsdifferent than those based on classical logical structures. I have studiedthis eld for some time, but I have had some questions along the way.I was looking at litotes (perhaps more exactly, antenantiosis), with formslikeHe is not unattractive.It is not impossible to do that.where the double-negation implies some form of a shift in meaning foreffect, following closely an empirical maxim sometimes called the divisionof pragmatic labor:The use of a longer, marked expression in lieu of a shorter expressioninvolving less efort on the part of the speaker tends to signal that thespeaker was not in a position to employ the simpler version felicitously(L. R. Horn, Duplex negatio afrmat... the economy of double negatives -- Chicago Linguistic Society 27-II)This kind of maxim, though, is very general, and would seem to point to manyof the other non-classically negated logics which still support the partialorder implied. This shows some sort of felicity with the agrammatical butcommon use of double negatives to stress negativity, such asThey don't know nothing!In the logical literature I have read, unfortunately, there is not as muchdistribution analyses of these logical models (for instance, thePerspectives der Analytischen Philosophie book Negation: a notion in focusedited by Heinrich Wansing), and so I was hoping someone might hold someclues as to:1) Are there any good tables available in the literature that correlatestypes and uses of negation with modern and historical languages? I mean, Iknow of some specic works such as The syntax of negation in russian bySue Brown, Buddhist theory of meaning (apoba) and negative statement byDhirenda Sharma, The grammar of negation by Jong-Bok Kim, and have readthings about Serbian and similar forms, but I'm very unsure of what isconsidered the most modern or agreed upon population correlations withfairly comprehensive scope.Additionally, I have been intrigued by the denial of terms found in theanvitabhidhana school, where negation is used to give a meaningful directionto action. For example, one may sayThe not-house will be builtTo stress the otherness or change for which the building is applied (as adistinguishing in the existing forms). This richness is an earlycontribution towards a typed theory of semantics. Su (la ilaha illa'llah) and taoist theories of negation are also quite sophisticated, and soI was curious about:2) are there also well known schools of thought about negation from Africanor South American traditions?-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: === prankster, fablist, magician, liarSubject: Re: the anticlassicalist }{ i: linguistic negation galathaea expression in lieu of a shorter expression : involving less efort on the part of the speaker tends to signal that the : speaker was not in a position to employ the simpler version felicitously : (L. R. Horn, Duplex negatio afrmat... the economy of double negatives -- : Chicago Linguistic Society 27-II) : : This kind of maxim, though, is very general, and would seem to point to many : of the other non-classically negated logics which still support the partial : order implied. This shows some sort of felicity with the agrammatical but : common use of double negatives to stress negativity, such as : : They don't know nothing!This is simply not true.This is not really a double negative.Compare with they don't know jack,they don't know diddly, orthey don't know squat.These are not double negatives and they all mean thesame thing.There is a relevant ellipsis here.If you include what is being left outthen all these are grammatical.If you go 49.9 miles then you have not gone50 miles. If there are 50 relevant facts andyou only know 49 of them then you don't know all 50.Suppose that instead of being merely relevant, thesefacts are basic. Then it could be truthfully said aboutthem (if they don't know All these facts) that they don't know the basics.The point in all these cases is that the ellipsis isabout some such phrase as as much as or even as muchas. The deep structure under the surface structure ofthey don't know x is they don't know an amount AS MUCH AS amount x,i.e., they know EVEN LESS THAN amount x.If I ask you for money and you reply, I won't give you a dime,you are not implying that there is some non-zero chance thatyou will give me a thousand dollars. What this rather means isI won't give you EVEN AS MUCH AS a dime, or equivalently,WhatEVER I give you, it will be LESS than a dime.They don't know *nothing*! (the exclamation pointDOES make a difference; it implies that my emphatic*'s around nothing were originally intended) is just a more intense version of all these other single-negativesinvolving a positive-yet-smaller-than-epsilon quantity.It is ultimate. In some cases there really is a differencebetween supplying a zero amount of something and not showingup to supply anything at all (i.e. giving somebody an emptybag and not even botherin to show up with a bag).RATHER than being a double negative, They don't know nothingREALLY means that they don't know even AS MUCH as nothing,that they know LESS than nothing, or that even allegingabout them that they MIGHT know an amount EVEN As small as 0is inappropriate; they are just not the kind of people towhom knowing IN GENERAL even COULD be ascribed. === Subject: Re: the anticlassicalist }{ i: linguistic negation -=-=-=-=-= linguistic negation =-=-=-=-=-=- The logic of natural language has been studied by many different schools avoided coming to any unique conclusionemphasizes the bankruptcy of the Liberal Arts. It's a hen party. Anybody can gossip and all are appreciated. It's bull. How wouldyou like to be doing 80 mph in a car that was built by mob ruleinstead of cold, hard, dry engineering?Oh, but that example is different! It certainly is. Liberal Arts arebull and engineering is real world.Everything in the Liberal Arts and Social Sciences is both right andwrong. No conclusion at all can be drawn except the need for morefunding. Say what you want - it makes no difference at all (exceptfor grant funding - then you must agree with the mob or be destroyed).Klingon was specically created to be the worst language possible byfolks who knew linguistics. It was enthusiastically embraced by themob and it is as good as Korean or Chinese for transferring content.--Uncle Alhttp://www.mazepath.com/uncleal/qz.pdfhttp:// www.mazepath.com/uncleal/eotvos.htm (Do something naughty to physics) === Subject: Re: the anticlassicalist }{ i: linguistic negation: >: > -=-=-=-=-= linguistic negation =-=-=-=-=-=-: >: > The logic of natural language has been studied by many That they have one and all avoided coming to any unique conclusion: emphasizes the bankruptcy of the Liberal Arts. It's a hen party.: Anybody can gossip and all are appreciated. It's bull. How would: you like to be doing 80 mph in a car that was built by mob rule: instead of cold, hard, dry engineering?:: Oh, but that example is different! It certainly is. Liberal Arts are: bull and engineering is real world.Formal linguistics is founded on the same rigour that onefinds in quantummechanics, so don't give me your bull. Obviously, I wouldn't trust alinguist to build my car solely on linguistic credentials, just as Iwouldn't trust a physicist to do surgery on me solely on the physicscredentials.in any way condemning science. I am scientist, and maybe if you stop yourre¤ex vomit and read a little, maybe one day you will become one too.I am talking about what we mean by making propositions in a model, and willbe discussing all sorts of wonders, like quantum logic, causal sets, andeven maybe explore antigen-antibody reactions. Yes, I will also be givingmany linguistic examples. I am sorry that I won't be able to respect thenarrow mindedness that you are so comfortable with.: Everything in the Liberal Arts and Social Sciences is both right and: wrong. No conclusion at all can be drawn except the need for more: funding. Say what you want - it makes no difference at all (except: for grant funding - then you must agree with the mob or be destroyed).:: Klingon was specically created to be the worst language possible by: folks who knew linguistics. It was enthusiastically embraced by the: mob and it is as good as Korean or Chinese for transferring content.Awww... I was hoping for a little more blatant racism from you. I can'thave any fun tearing you a new one with that tired rag.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ i: linguistic negation : >> : > -=-=-=-=-= linguistic negation =-=-=-=-=-=-> : >> : > The logic of natural language has been studied by many different schools> of> : > and all avoided coming to any unique conclusion> : emphasizes the bankruptcy of the Liberal Arts. It's a hen party.> : Anybody can gossip and all are appreciated. It's bull. How would> : you like to be doing 80 mph in a car that was built by mob rule> : instead of cold, hard, dry engineering?> :> : Oh, but that example is different! It certainly is. Liberal Arts are> : bull and engineering is real world. Formal linguistics is founded on the same rigour that onefinds in quantum> mechanics, so don't give me your bull. has pulled adonut about itself. It proposes to follow scientic method ondatabases that are at best weakly statistical and that have noempirical falsication possible, inputs or outputs. Like psychology,it shouts its self-percieved triumphs and whimpersheteroskedasticity at its failures. BTW, what are linguistics'triumphs?Well I don't think it's quite fair to condemn a whole program becauseof a single slip-up, sir. General Buck Turgidson explaining to thePresident the psychological evaluation program whose slip-up wasGeneral Ripper's 34-plane airborne nuclear attack upon Russia. --Uncle Alhttp://www.mazepath.com/uncleal/qz.pdfhttp:// www.mazepath.com/uncleal/eotvos.htm (Do something naughty to physics) === Subject: Re: the anticlassicalist }{ i: linguistic negation: > Formal linguistics is founded on the same rigour: > that onefinds in quantum mechanics, so don't: > give me your hole that has pulled a: donut about itself. It proposes to follow scientic method on: databases that are at best weakly statistical and that have no: empirical falsication possible, inputs or outputs. Like psychology,: it shouts its self-percieved triumphs and whimpers: heteroskedasticity at its failures. BTW, what are linguistics': triumphs?Well, the rst and most apparent of all triumphs has been the ability toformalise and rigorise communication to avoid the ambiguity of everyday talkand create that useful thing called science. Logical linguistics andsemiotics has abstracted in many different directions, including describingthe foundations of mathematics and the logical structure of scienticmodels. It is also able to describe a lot of structure in natural language,but I don't want to distract you.There is even a lot of research mapping neural connections, crammingelectrodes into the brains of various eumetazoan critters, determiningglucose consumption through radiological methods, or nicely detailing RNAexpression or neurotransmitter response to freshly sliced brain sections ofvarious experimental subjects. You can block your eyes and plug your earsall you want, but there is already a quite large and developing communitystudying the origin of auditory and visual symbolic processing in the brain,and strangely enough, we already have the beginnings of linguisticexpression forming in the research. And they match quite nicely withlogical linguistic research that formal languages are built on.So where do you cut the line, mister scientist? Where do models stop,through whatever mystical explanation you care to provide, being able toaccurately represent reality? Have you not seen the quite accurate modelsthat ll research proceedings every year on modeling various brain regions?You could even use your amazing snipped all the references to math and physics, perhapsindicative that you never wanted to engage in meaningful dialectic? That istypical for one such as yourself who considers their daily minesweeperpractise innitely more useful to society than the farm workers who'scitizenship may be questioned.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: === prankster, fablist, magician, liarSubject: Re: the anticlassicalist }{ i: linguistic negation > BTW, what are linguistics'> triumphs?You are my good Sir, and so is the Universe and everything,even 42. Allow me to prove it... , that's the Bookof Mormon... Urantia Book? no.. where are my Gideons' Bibles when I need them? This will have to do:L'.8evangile selon Saint JeanAu commencement le Verbe .8etait et le Verbe .8etaitavec Dieu et le Verbe .8etait Dieu. Il .8etait aucommencement avec Dieu. Tout fut par lui etsans lui rien ne fut.Voil.88. On ne saurait .90tre plus clair: in the beginning was the Word and the Word was withGod and the Word was God. The Word was in thebeginning with God, and by Him/It all was made,and without Him/It nothing. (or something tothat effect).There, Sir, lies the Triumph of Linguistics.Hors la linguistique, point de salut, c'est clair.Beat that! === Subject: Re: the anticlassicalist }{ i: linguistic negationgalathaea > The logic of natural language has been studied> by many different schools of thought throughout history.> Much of this study has pointed to many models> different than those based on classical logical structures.> I have studied this eld for some time, but I have had some> questions along the way.>> I was looking at litotes (perhaps more exactly, antenantiosis),> with forms like>> He is not unattractive.> It is not impossible to do that.>> where the double-negation implies some form of a shift> in meaning for effect, following closely an empirical maxim> sometimes called the division of pragmatic labor:>> The use of a longer, marked expression in lieu of a shorter> expression involving less efort on the part of the speaker tends> to signal that the speaker was not in a position to employ the> simpler version felicitously> (L. R. Horn, Duplex negatio afrmat... the economy of double> negatives -- > Chicago Linguistic Society 27-II)>> This kind of maxim, though, is very general, and would seem> to point to many of the other non-classically negated logics> which still support the partial order implied. This shows some> sort of felicity with the agrammatical but common use of> double negatives to stress negativity, such as>> They don't know nothing!>> In the logical literature I have read, unfortunately, there is> not as much distribution analyses of these logical models> (for instance, the Perspectives der Analytischen Philosophie> book Negation: a notion in focus edited by Heinrich> Wansing), and so I was hoping someone might hold some> clues as to:>> 1) Are there any good tables available in the literature> that correlates types and uses of negation with modern> and historical languages? I mean, I know of some specic> works such as The syntax of negation in russian by> Sue Brown, Buddhist theory of meaning (apoba) and> negative statement by Dhirenda Sharma, The grammar> of negation by Jong-Bok Kim, and have read things> about Serbian and similar forms, but I'm very unsure> of what is considered the most modern or agreed upon> population correlations with fairly comprehensive scope.>> Additionally, I have been intrigued by the denial of terms> found in the anvitabhidhana school, where negation> is used to give a meaningful direction to action.> For example, one may say>> The not-house will be built>> To stress the otherness or change for which the building> is applied (as a distinguishing in the existing forms).> This richness is an early contribution towards a typed> theory of semantics. Su (la ilaha illa .95llah) and taoist> theories of negation are also quite sophisticated, and> so I was curious about:>> 2) are there also well known schools of thought> about negation from African or South American> traditions?--------------------------------------------------- --------------They speak mostly Spanish in South America.In Spanish, double-negatives are required.It has nothing to do with logic. It's just amatter of grammatical agreement:http://spanish.about.com/library/weekly/ aa061101a.htm~I don't know if legalese-Spanish is any different.~People frequently make positive assertions,such as this is really great..., while at thesame time shaking their heads as if denying it.When I rst started noticing that, I couldn'tthink of any explanation for it other thanthat it was probably a parapraxix, like a slipof the tongue, -revealing that they were lying.But that can't possibly be it.Whatever the true explanation, I think ithas something to do with how we constructsentences unconsciously. I think we constructin parts, in parallel, many different ways to saya thing, and then, at the last second,choose one of them to speak. And I thinkwe always construct both positive andnegative ways to say it. And then, if wechoose to speak the positive form, ourheads may shake to negate, -not it, - butthe lingering unspoken (.95undischarged'perhaps) negative form.I believe negation of sentences wasone of the things Chomsky had in mindas a surface-structure transformation,-meaning that it is a trivial last-secondtransformation made on a deep-structureconstruct. Which would only make senseif the deep construct was un-ambivalent,- perhaps even always positive. But Ibelieve that Chomsky eventually gaveup that approach.~Different cultures use differenthead motions to signal .95yes' and .95no'.In India they bob their heads tosay .95yes' -in a way that looks toothers like .95no'. Italians jerktheir head up once to say .95yes',- in a way that looks to otherslike they want to start a ght.(- Some may recall images ofMussolini .95chilling' - crossinghis arms and jerking his headup after giving a speech;He wasn't looking for a ght;He was just pleased with himself.)Desmond Morris talks aboutgesture frontiers, or isoclines.And isoclines of yes/no gesturescross each other in the Balkans.That, and the suspicion that body-languagethat appears to contradict the spoke languageimplies that the person is lying - may goa long way to account for the Balkans.No one understands any one there.~~Sartre regarded negation as the primarycharacteristic of being human: .... from a web page: -- On Part One of Being and Nothingness: Nothingness and Bad Faithhttp://216.239.51.104/search?q=cache:Vp5XSEbyWXgJ: web.ics.purdue.edu/~mmichau/sartre-bn.pdf+%22Being+And+ Nothingness%22+negation&hl=en&ie=UTF-8 I. The Origin of Negation In this section, Sartre discusses the relation between being-in-itself and being-for-itself. Probably the most original feature in Sartre's conception of consciousness is his insistence on its essential negativity; neither Husserl nor Heidegger gives the negative function such a central place ii. In BN we begin with a sober analysis of investigation as called for by the ontological problem, similar to the discussion of Being in Being and Time. However, in Sartre's work, the main emphasis is on the readiness to be faced by the non-existence of the situation inquired about. The question thus reveals that nothings are constant possibilities of our experience. In fact consciousness is shot through with nothings; Nothingness is an immanent characteristic of Being.etc.~~> It is not impossible to do that. ...> The use of a longer, marked expression in lieu of a shorter> expression involving less effort on the part of the speaker tends> to signal that the speaker was not in a position to employ the> simpler version felicitouslyI don't buy less effort playingany role at all in natural speech.People think at a xed rate. And they also speak atsome xed rate appropriate to circumstance. Normally,speech is massively redundant and contentless. Speechis, I think, just a vestigial behavior originating in ourmonkey ancestor's primary social bonding behaviorcalled lice picking. We don't carry lice anymore,or don't admit it, and, therefore we have to talk toeach other instead. And so, there's just no pointinfinding ways to say things with .95less effort'.There's certainly a connotational difference between: It is possibleand It is not impossible.However, it's not perfectly clearto me what it is, at this moment.~> So I still am left asking:> 3) what is the actual source of the bias against nonclassical logics?Try: Deviant Logic, Fuzzy Logic: Beyond the Formalism -- by Susan Haackhttp://www.amazon.com/exec/obidos/tg/detail/-/0226311341/ qid=1077019274/sr=1-1/ref=sr_1_1/102-7545475-4339367?v=glance& s=books~Greg. === Subject: Re: the anticlassicalist }{ i: linguistic negation:: They speak mostly Spanish in South America.:: In Spanish, double-negatives are required.: It has nothing to do with logic. It's just a: matter of grammatical agreement:: http://spanish.about.com/library/weekly/aa061101a.htm: ~:: I don't know if legalese-Spanish is any different.: ~This distinction between negation of objects and negation of actions seemsto have lead to a rich variety of negations in various languages. I don'tknow why I didn't mention Spanish, but I hear this all the time and make theappropriate conclusion quite readily. I think this may be common inPortuguese as well, as I have a Brazillian friend who uses it quite often(though the language is so pretty, its sometimes hard to hear the languagefor the song).(though, I will have to check again, since I really was looking for it). Itis much more formal and strives to be clear.: People frequently make positive assertions,: such as this is really great..., while at the: same time shaking their heads as if denying it.:: When I rst started noticing that, I couldn't: think of any explanation for it other than: that it was probably a parapraxix, like a slip: of the tongue, -revealing that they were lying.:: But that can't possibly be it.Sure it can! But it seems it could also be an indication of an internalstruggle elicited by the surprise, as if the internal model needs updatingbecause of the inconsistency. Which you..: Whatever the true explanation, I think it: has something to do with how we construct: sentences unconsciously. I think we construct: in parts, in parallel, many different ways to say: a thing, and then, at the last second,: choose one of them to speak. And I think: we always construct both positive and: negative ways to say it. And then, if we: choose to speak the positive form, our: heads may shake to negate, -not it, - but: the lingering unspoken (.95undischarged': perhaps) negative form.:: I believe negation of sentences was: one of the things Chomsky had in mind: as a surface-structure transformation,: -meaning that it is a trivial last-second: transformation made on a deep-structure: construct. Which would only make sense: if the deep construct was un-ambivalent,: - perhaps even always positive. But I: believe that Chomsky eventually gave: up that approach.:: ~... point out yourself, in a way. There is certainly a complex selectiveprocess in the construction of our communication. Negation may be a trivialtransformation sometimes, but I believe there are many situations where itsintent is more subtle and must be inferred from other clues of theconversation, perhaps nonverbal ones like you mention.: Different cultures use different: head motions to signal .95yes' and .95no'.: In India they bob their heads to: say .95yes' -in a way that looks to: others like .95no'. Italians jerk: their head up once to say .95yes',: - in a way that looks to others: like they want to start a ght.: (- Some may recall images of: Mussolini .95chilling' - crossing: his arms and jerking his head: up after giving a speech;: He wasn't looking for a ght;: He was just pleased with himself.):: Desmond Morris talks about: gesture frontiers, or isoclines.: And isoclines of yes/no gestures: cross each other in the Balkans.:: That, and the suspicion that body-language: that appears to contradict the spoke language: implies that the person is lying - may go: a long way to account for the Balkans.: No one understands any one there.:: ~~Ahh, the balkanisation of negation! Such a combative view of nonclassicaltheories of negation...With so much to worry about in utterances and visual symbolics, gesturevariation seems so much more... easily acceptable? Although I do like tolook at faces closely, Ifind I rarely see gestures as anything offensivewhen I understand the speak. This seems a common trade-off ininterpreting communication, though you bring up powerful points about realintent often found in the unspoken.:: Sartre regarded negation as the primary: characteristic of being human: ....:: from a web page: --: On Part One of Being and Nothingness:: Nothingness and Bad Faith:http://216.239.51.104/search?q=cache:Vp5XSEbyWXgJ: web.ics.purdue.edu/~mmichau/sartre-bn.pdf+%22Being+And+ Nothingness%22+negation&hl=en&ie=UTF-8:: I. The Origin of Negation: In this section, Sartre discusses the relation: between being-in-itself and being-for-itself.: Probably the most original feature in Sartre's: conception of consciousness is his insistence: on its essential negativity; neither Husserl nor: Heidegger gives the negative function such a: central place ii. In BN we begin with a sober: analysis of investigation as called for by the: ontological problem, similar to the discussion: of Being in Being and Time. However, in Sartre's: work, the main emphasis is on the readiness to be: faced by the non-existence of the situation inquired: about. The question thus reveals that nothings are: constant possibilities of our experience. In fact: consciousness is shot through with nothings;: Nothingness is an immanent characteristic: of Being.::: etc.: ~~I wasn't sure whether or not to bring up Sartre, and I regret that. Ishould have been more eager to include his work in the schools of negation Iam studying. I keep letting the biases of some so-called scientists on theboards affect the focus of my this up.Negation as primary in cognitive notions of existence against nothingnessdoes seem to have some type of primary place in our conceptualisationhidden negations used in identication processes. I also believe that thisline of reasoning describes how even rst-order logics rely uponsecond-order notions implicitly passed off to the user, and I should tie all: > It is not impossible to do that. ...: > The use of a longer, marked expression in lieu of a shorter: > expression involving less effort on the part of the speaker tends: > to signal that the speaker was not in a position to employ the: > simpler version felicitously::: I don't buy less effort playing: any role at all in natural speech.:: People think at a xed rate. And they also speak at: some xed rate appropriate to circumstance. Normally,: speech is massively redundant and contentless. Speech: is, I think, just a vestigial behavior originating in our: monkey ancestor's primary social bonding behavior: called lice picking. We don't carry lice anymore,: or don't admit it, and, therefore we have to talk to: each other instead. And so, there's just no point: infinding ways to say things with .95less effort'.:: There's certainly a connotational difference between::: It is possible:: and:: It is not impossible.:: However, it's not perfectly clear: to me what it is, at this moment.: ~I think the effort is found in the moving of the decision to one that isconscious. The example of Spanish shows that negative elements are added ina negative scope quite easily by those who habituate the negative form. Butthere are certain expressions that are not common, and are clear in acontext to have been chosen for a reason. I wouldn't put they don't knownothing in that group, but I would usually put it is not impossibleunless I was speaking to someone who has completely habituated suchambiguity defensively.Whether an afrmation or a negative seems more ¤uid or subconscious in agiven context is certainly difcult to objectively test, but I do believethere are indicators found in patterns of speech which help us judge ifsomething was thought about more deeply before being uttered.:: > So I still am left asking:: > 3) what is the actual source of the bias against nonclassical logics?::: Try:: Deviant Logic, Fuzzy Logic: Beyond the Formalism: -- by Susan Haack::http://www.amazon.com/exec/obidos/tg/detail/-/ 0226311341/qid=1077019274/sr=1-1/ref=sr_1_1/102-7545475- 4339367?v=glance&s=booksI had that book in my hands about three weeks ago, but decided not to checkit out in favor of some other readings. My local university library has twocopies, so I should be able to get that later on today when very helpful.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ i: linguistic negation~greg >> ...> Whatever the true explanation, I think it> has something to do with how we construct> sentences unconsciously.Meant .95subconsciously'.(I write posts .95unconsciously'.) === Subject: Re: the anticlassicalist }{ i: linguistic negationNow really, Ms.(?) fabulist, etc: there is much that is more grosslyinappropriate to sci.physics here, so you might say all the other kidsare doing it. But if you affect to be a _superior_ kid, might you notlead by example and limit the number of freshly cross-posted threadswhich are mainly about linguistics, and neither physics nor math?You are beginning to speak Crankish.> -=-=-=-=-= linguistic negation =-=-=-=-=-=- The logic of natural language has been studied by many different schools of> thought throughout history. Textual analysis: schools of thought do not study anything, and is acliche.For somebody who is so academically concerned with language, you seemremarkably insensitive to its use. Your earnestly learned turgiditywill carry you far ... away from here. === Subject: Re: the anticlassicalist }{ i: linguistic negation:: Now really, Ms.(?) fabulist, etc: there is much that is more grossly: inappropriate to sci.physics here, so you might say all the other kids: are doing it. But if you affect to be a _superior_ kid, might you not: lead by example and limit the number of freshly cross-posted threads: which are mainly about linguistics, and neither physics nor math?:: You are beginning to speak Crankish.There is certainly math already in what I've posted. Although a couplegroups have dropped either iv or v of the series (at least from what I'veseen on my server), there is already the beginnings of an exposition onlattice theory. And my focus is on getting to quantum logic, the study ofcausal sets, and logics for reasoning about continuous dynamics here in thestart talking about model satisfaction somewhere, to nish the foundations,but I understand that physicist may still be wary about applicability totheir own models, so I may invert the discussion some.I intended only two threads so far. The rst was to be towards aconstructive education, which was to be quite largely cross posted (thoughwell within the scope of all groups I posted to) in order to draw in theopinions from what I knew to be a quite small minority in each eld, butunfortunately found that newsservers have maximum cross-posting limits, so Ineeded to repost in a chopped up fashion, for which I appologise. Along theway, I came up with the starting of an organised bibliography, which I triedto post in the same thread as my rst. Unfortunately, I believe one of thethe other two sections of posts for towards a constructive educationgroups to post for this section, and that particular posting software brokeit out of the thread even though I replied within.Then I have this thread, the anticlassicalist where I wanted to expand onthe things that people had asked questions about in my rst thread. Thissci.physics.research. It is meant to be educational as well as provocative.It is certainly meant to raise the level of discourse from the potty mouthedname calling so clogging sci.physics, and is meant to introduce linguists tothe logical formalisation which was so heavily questioned in my rstthread. The logicians have had some arguments about these topics, so Iwanted to enter the fray, and nearly all of my exposition will bemathematical when I am not questioning psychological motives.So, I believe my post targets are accurate, and I have only managed to start4 threads total in the process. 2 of those were incidental, not intended.Unlike cranks, I am open to critical analysis and earnest debate.: > -=-=-=-=-= linguistic negation =-=-=-=-=-=-: >: > The logic of natural language has been studied by many different schoolsof: > thought throughout history.:: Textual analysis: schools of thought do not study anything, and is a: cliche.:: For somebody who is so academically concerned with language, you seem: remarkably insensitive to its use. Your earnestly learned turgidity: will carry you far ... away from here.Ok, I change it to read only schools. That was more my intention.As for turgidity, I do understand that my writing can be up tight attimes, just as sometimes it can be more playful. When I look to thesegroups, however, I see that often the angry rebuttals cause either crankishobstinacy or a learned timidity. The timidity response places those wholaunched the angry rebuttals into authoritative positions that often I donot feel they have the competency for. Uncle Al is a prime example of onewho certainly is knowledgeable, but is also quite ignorant and certainly notone I see as an authority.I've studied obsessively for many years, and will continue doing so for manymore. Any condence that comes through in my posts is due to muchpractise, but I do not want to convey that such condence excludes memaking mistakes or accepting their being pointed out. I know I makemistakes all the time. I focus on them, to try to understand them. But Iwill not back down from my positions by content-less chest beating.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ i: linguistic negation > Now really, Ms.(?) fabulist, etc: there is much that is more grossly> inappropriate to sci.physics here, so you might say all the other kids> are doing it. But if you affect to be a _superior_ kid, might you not> lead by example and limit the number of freshly cross-posted threads> which are mainly about linguistics, and neither physics nor math?Here at sci.lang, we sure haven't seen many posts about linguistics,other than one indicating she'd once opened a volume of Proceedings.> You are beginning to speak Crankish. > -=-=-=-=-= linguistic negation =-=-=-=-=-=->> The logic of natural language has been studied by many different schools of> thought throughout history. Textual analysis: schools of thought do not study anything, and is a> cliche. For somebody who is so academically concerned with language, you seem> remarkably insensitive to its use. Your earnestly learned turgidity> will carry you far ... away from here. Evidence that she's academically concerned with language?-- Peter T. Daniels grammatim@att.net === Subject: Re: the anticlassicalist }{ i: linguistic negatio > They don't know nothing!>How bland. Let's really mean it: They don't know nothing about nothing.> The not-house will be built>Is this to mean the not-house won't be not-built.Do even number of negations afrm and odd number of negations deny? If he didn't not double negate, didn't he afrm? If he didn't not double negate, didn't he not afrm?How about double afrmatives implying negation?Aren't my ideas the greatest?Oh yea, yea. === Subject: Re: the anticlassicalist }{ i: linguistic negation: 2) are there also well known schools of thought about negation fromAfrican: or South American traditions?I didn't mean to appear to exclude the su as a part of African thought,but intended other schools of thought only because of familiarity.Syncretism, particularly from gnostic schools, seems to be a fertile groundfor such thought, but I was thinking more of the Ishango bone or khipu andwondering of symbolic negation work in societies in¤uenced by these andother early symbolic mathematics.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ i: linguistic negation >> I was looking at litotes (perhaps more exactly, antenantiosis), with forms> like>> He is not unattractive.> It is not impossible to do that.>> where the double-negation implies some form of a shift in meaning for> effect, following closely an empirical maxim sometimes called the division> of pragmatic labor:>Do not double negatives not leave you tied in knots? === Subject: Re: the anticlassicalist }{ i: linguistic negation: Do not double negatives not leave you tied in knots?It is eerie how I was typing up a question about the khipu at the same timeyou posted.Is it knot?(PS: Louis Kauffman has some beautiful stuff on knot logics, as well.Reminds me of the BBC / TimeLife show Connections with James Burke)-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ i: linguistic negation > : Do not double negatives not leave you tied in knots? It is eerie how I was typing up a question about the khipu at the same time> you posted. Is it knot?Anglice, .> (PS: Louis Kauffman has some beautiful stuff on knot logics, as well.> Reminds me of the BBC / TimeLife show Connections with James Burke) --> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- galathaea: prankster, fablist, magician, liar-- Peter T. Daniels grammatim@att.net === Subject: Re: the anticlassicalist }{ i: linguistic negation -=-=-=-=-= linguistic negation =-=-=-=-=-=- The logic of natural language has been studied by many different schools of> thought throughout history. Much of this study has pointed to many models> different than those based on classical logical structures. I have studied> this eld for some time, but I have had some questions along the way. I was looking at litotes (perhaps more exactly, antenantiosis), with forms> like He is not unattractive.> It is not impossible to do that. where the double-negation implies some form of a shift in meaning for> effect, following closely an empirical maxim sometimes called the division> of pragmatic labor: The use of a longer, marked expression in lieu of a shorter expression> involving less efort on the part of the speaker tends to signal that the> speaker was not in a position to employ the simpler version felicitously> (L. R. Horn, Duplex negatio afrmat... the economy of double negatives --> Chicago Linguistic Society 27-II)If you like Larry's short paper, you might want to look at his book, *ANatural History of Negation*. He's the leading expert on the topic.-- Peter T. Daniels grammatim@att.net === Subject: Re: the anticlassicalist }{ i: linguistic negation: If you like Larry's short paper, you might want to look at his book, *A: Natural History of Negation*. He's the leading expert on the topic.The descriptions of that book look very, very promising, suggestion; I will pickit up tomorrow!-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: === prankster, fablist, magician, liarSubject: Re: the anticlassicalist }{ i: linguistic negation At least, Franz Gnaedinger has something to say when he talks tohimself. Or are you the latest avatar of Archimedes Plutonium? === Subject: Re: the anticlassicalist }{ ii: the spectre continues-=-=-=-=-= the spectre continues =-=-=-=-=-=-Now, with this long history of logical analyses of language, I alwaysfindit strange that there are comments like:Attention being devoted here entirely to the classical two-valued theoriesof truth-functions, quantiers, and identity, with syntax, semantics, andpragmatics built upon their basis, there will be no concern with alternativeforms of logic, so-called three-valued (or, more generally, n-valued)logics, modal logics, intuitionist logics, and the like. The view is thatwhatever is valuable in these alternatives can be achieved more readilywithin the classical framework by suitable extensions.in the introduction to Semiotics and linguistic structure by R. M. Martin,where such a representation is not faithful to actual usage or expression.Now, I just recently posed some questions on the newsgroups concerningnonclassical logic, and certain linguists and physicists were actually quiteconfrontational about the idea of educating about these nonclassical logics.Expressibility was always proffered as a reason, even though no one can evenclaim that boolean is rich enough).So I still am left asking:3) what is the actual source of the bias against nonclassical logics? Istill look at classical logic and I see Aristotle and Western thought inphilosophy and mathematics, but I don't see it representing the way peopleverbally reason about the world usually. Why must there be one and only onelogic of language? So much so that there was an aggression in theresponses, as if not only is that one useful, but that it is the one thatall people must speak.Because I see many other, often non-Western, traditional schools of meaningand language with much more faithful representations of actual usage, and Iwonder why the bigotry? As if the schools most in¤uenced by Aristotelianideas must control the way we think about the world? I look to work byKorzybski and see something ominous about this desire to control theontology and mechanics of the way we reason about the world. It isunderstandable where the Polish school of logic and ontological theory comesfrom.And there is the concordance between Aristotle's work in full, betweenlogic, ethics, and an abstract monotheism, that has made his workin¤uential in Jewish, Islamic, and Christian traditions, but less so inpolytheistic traditions, so provocateur that I am, I still believe there issomething here.The quote from Martin even continues quite explicitly:Strictly, there is only one logic, which, however, can be extendedvariously for specic purposes as needed. .95One god, one country, onelogic,' is the stunning phrase of Whitehead.The rst-order or elementary point of view is pressed in this book, not asfar as possible perhaps, but a good deal further than is usually supposedpossible. The reader mayfind himself surprised to see how much can beachieved on so narrow a basis. God made rst-order logic and all the restis the handiwork of man.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: === prankster, fablist, magician, liarSubject: Re: the anticlassicalist }{ ii: the spectre continues galathaea continues =-=-=-=-=-=- : : Now, with this long history of logical analyses of language, I alwaysfind : it strangeWell, it is not strange.You are ¤aunting ignorance here. : that there are comments like: : : Attention being devoted here entirely to the classical two-valued theories : of truth-functions, quantiers, and identity, with syntax, semantics, and : pragmatics built upon their basis, there will be no concern with alternative : forms of logic, so-called three-valued (or, more generally, n-valued) : logics, modal logics, intuitionist logics, and the like. The view is that : whatever is valuable in these alternatives can be achieved more readily : within the classical framework by suitable extensions. : : in the introduction to Semiotics and linguistic structure by R. M. Martin, : where such a representation is not faithful to actual usage or expression.Actual usage or expression is just irrelevant. Unless you are a linguistwhose object of study is how real people use natural language, naturallanguage IS JUST STUPID, because PEOPLE are just stupid. : Now, I just recently posed some questions on the newsgroups concerning : nonclassical logic, and certain linguists and physicists were actually quite : confrontational about the idea of educating about these nonclassical logics. : Expressibility was always proffered as a reason, even though no one can even : claim (lambda : calulus is rich enough).The parenthetical statement is incredibly stupid. Lambda calculus is BIGGER AND BADDER than classical boolean anything; it is MOREcomplex. SO OF COURSE it is rich enough to expresswhatever. That is not even the question. The questionis whether you can achieve similar expressiveness withSIMPLER machinery (like classical boolean algebra).There is, after all, a set of rst-order axioms deninglambda-calculus. === Subject: Re: the anticlassicalist }{ ii: the spectre continues> There is, after all, a set of rst-order axioms dening> lambda-calculus.Do you know of any online presentations?:-)mitch === Subject: Re: the anticlassicalist }{ iii: cognitive property maps-=-=-=-=-= cognitive property maps =-=-=-=-=-=-However, I have also learned that many are just unfamiliar with otherlogical systems, so I wanted to also give a brief introduction to lattices,logic, and models, to clarify my points.Lets start with some objects we've collected. We have this ability toabstract out properties of these objects that shows some commonalities,Let's name them, by attaching a string of symbols to each object andproperty we can identify (or pattern recognise).Objects: # $ % $# $$Properties: $% %# %$ %%Now lets say that we are able to form certain relationships between theproperties and the objects, as in we can illustrate the relationship of anobject having a certain property. We can do this by drawing an arrow fromthe property list names to the object list names that have the property.# $ % $# $$^ % % _*& ;%@| / / _ / { ~ /| / /_ / ~ ( /$% %# %$ %%Or, more clearly, you have$% pointing to # and $%# ... % $# and $$%$ ... $# $$%% $# $$Youfind a useful way to group these things by drawing more arrows when allof an objects properties are also properties of a second object, and in adual fashion whenever a property points to all objects that another propertypoints to, because this expresses the ability to tell the classicationtypes apart. In other words,Both # and $ are pointed at by $% and only $%, so they both point to eachother:# <-> $and maybe we can't really think of the property that we thought told themapart to name them differently. So we collapse them to one name =.Since %# points to all three %, $#, $$ where %$ and %% point to only $# and$$, we have $# <-> $$ ^ & % ^ | X | | / |% $% <-> %% & ^ % | / | / %#and we realise we never were able to tell $% and %% apart, just as we neverwere able to tell # and $ apart, and similarly we admit that we cannot tell$# and $$ apart. You've forgotten what it was you had thought you saw thatmade you name them different things, which happens when you have so manythings to remember. The objects have all the same properties ($% and %%),the properties all the same objects.We collapse the objects and properties and no longer make any distinctionbetween objects and properties; the two collapsed names are chosen to be Aand E.Mathematicians would say: A collapse starts with an equivalencerelationships and takes what is known as a quotient by naming theequivalence classes.Let's say that some smart, bunny-looking thing walks up to you one day andconvinces you of the utility of drawing a new arrow anytime you have twoarrows head to tail the same name location. This bunny looking thing is amagician of great power who calls this creation composition with eloquentarticulacy, and you learn to see the bunny operation as giving the arrows amotion or dynamics of meaning.What we are left with is:=^||$%% E --> A & ^ % | / | / %#This seems to be a really interesting way to think about the world, becauseit seems to let us classify. We organise our thoughts and see relationshipsbetween the various things we identify in the world. Those arrows(admittedly poorly rendered in xed point ASCII) or morphisms or whateveryou call them point from one pattern you can recognise to another patternyou can recognise that distinguishes itself by _adding_ recognition rules(ie. the rules of the tail object are also rules of the head object).And rules is just a name for properties or identiable traits oranything that abstractly obeys the rules we establish for it. There aremany ways of interpretation, and that freedom allows us to read muchexpressiveness into these fundamental relationships.Its a great way to map the world.We could even start naming the arrows and having lots of arrows betweenobjects where we suddenly get the richness of language, of noun and verb, ofobject and transformation. However, lets look more at what we have above.other name, there is always either one or none arrows pointing from theformer to the latter. And anytime we have no procedure to tell objectsapart, we have collapsed them into a new name.Some hippy stoner dude came along and convinced you that every name wasreally an arrow pointing at itself, which he called the identity morphism,maaaan. It doesn't make any difference whether you think of objects ortheir identity morphism as primary since they both can represent the samerelationships, so there's nothing committed by the idea.What we've got, the mathematicians call a skeletal pre-order catgeory or aposet. We can call it whatever we want in our own pidgin, so I'll justcall it a map with emphasis on the objects of cognitive recognition. Theconnection between the acyclic digraphs found in recognition problems andposets is detailed furthur by Monique Pavel in Fundamentals of patternrecognition: 2nd edition, revised and expanded.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ iv: from maps to logic-=-=-=-=-= from maps to logic =-=-=-=-=-=-Now let us look at interpretting this arrow symbol, such as in process,categorial inclusion, rule renement, or progressions of state. We wantto be able to evaluate logical relationships between objects. So we look todene on a recognition map new objects dened by any two objects whichallows us to collectively compare two objects logically. The rst one ofthese, which can be called the least upper bound or disjunction of twostates .95a' and .95b', written (a / b) which obeys the rules thata -> (a / b)b -> (a / b)forall x in the lattice with a -> x and b -> x, we have (a / b) -> xwhere it is important to differentiate when these are derivationally foundon a lattice (objects already dened through previous axioms with theappropriate universal property derivable) and when the existence of newobjects is being dened (for each new denition requires new consistency /completeness / etc. checks). Universals have interesting dualities withexistential denitions (as seen in all of the there-exists hidden abovewhen not derivationally found), but I don't want to explore those here interms of the metalanguage. These denitions are fairly safe, with manyconsistent models.These disjunctions are unique after recognition collapse and capture theidea that, whatever the arrow is interpreted as, there is an object in thismap for any pair of objects with a universality property of being pointedat by the pair and pointing at any others also pointed at by the pair.It captures the conceptual operations of joining concepts, collecting, orunion, and is abstractly what is known as a coproduct.In linguistics, this corresponds to an abstract representation of what iscalled in English or (with inclusive semantics) when we are focused onrecognition and property inclusion.There is also an operation that has a duality to the coproduct by ¤ippingthe arrows around and giving it the name .95/'. So the dention in terms ofa pair of objects .95a' and .95b' is merely:(a / b) -> a(a / b) -> bforall x in the lattice with x -> a and x -> b, we have x -> (a / b)with again existence implied when not constructed.This operation has names like conjunction, greatest lower bound, or moresimply product. It expresses a description of where concepts meet intheir description. In English, this is an abstraction of and in therecognition / property inclusion interpretation.With the structure dening product and coproduct objects for all pairs ofobjects in the poset, we have what is known as a lattice. The lattice hasdual connections or operations (/, /) with particular universal(forall) relations in a variable over the lattice. An algebra can beattached.These begin the logical theories of and and or, conjunction anddisjunction, coproduct and product.-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Re: the anticlassicalist }{ v: universal truths-=-=-=-=-= universal truths =-=-=-=-=-=-We can even dene another object _|_ with the universal property:forall x in the lattice, we have _|_ -> xand a dual object T withforall x in the lattice, we have x -> T,where again it is important to point out the implied existential axiom ifnot derivable. These give us two useful identities on which to focus workin models. Yes / no classication in models have been very benecial, andmuch of our languages use them readily and often. But notice we still havealot of freedom in the logic (there are no restrictions on the existence ofother objects besides T and _T_, for example, and many logics use otherobjects in this framework), and models that lack these completeness objectsare still useful.Let me give a little example of the calculus of denition on these latticesthat can illustrate how the lattices help us describe our ability to modelrelationships we observe. Given a lattice, we can choose one object (let'scall it P) standing for something in the ontology and add the axiom thatT -> P. Then when we collapse the lattice to skeletal form (since now T <->P and are the same thing represented under two names, with .95T' kept), we maynd a cascade of collapses if P pointed to any other objects (say Q1, Q2,...) wil each in turn <-> T. So as we dene structure on the lattice, wecan represent different models of the interactions of these universalobjects (_|_ and T, whatever interpretation may be given them) with otherpropositions on the lattice.And on these lattices we can make more explicit our theories of negation.On sci.logic, mitch recently gave a very interesting post on Stone algebras.When we want to model uses of various denitions, we need to show them asan axiom set. Stone algebras study the axiom set:~(a) / ~(~(a)) <--> Twhere ~() is a mapping from the lattice into itself. There are manyconsistent lattices that have mappings that obey this axiom. As mitch'sinto ideals of atomic boolean lattices which also classify throughembedding pseudocomplemented distributive lattices, and that there is aknown hierarchy between boolean lattices and pseudocomplementeddistibutive lattices which include the lattices that obey the Stone axiom.So this axiom denes a class of logics somewhere between the boolean worldand lattices that are pseudocomplemented and distributive.These two terms are dened as structural axioms of the lattice. A latticethat is pseudocomplemented has dened for every object .95a' another object'a*' with the propertyforall x in the lattice with (x / a) <-> _|_, we have x -> a*whereas a lattice that is distributive obeys the axiomfor all x, y, and z in the lattice, we have x / (y / z) <-> (x / y) / (x/ z)and we can start to attach meanings to these kinds of lattices byunderstanding the universal properties implied. Theyfind uses in trigeringcollapse operations on the lattice during derivations or deductions in thestructure. The pseudocompliment gives a universal disjoint property tonegation. Distributivity gives a well known algebraic relationship betweenany three objects of the lattice, and I will later show that quantum logicsare examples of logics that are not distributive.So we start to see the rich world of lattices and meaning, slowly. Othernegations than those mentioned above can be explored. There are subminimal,preminimal, and minimal negations. There is de Morgan, intuitionistic, andortho negation.Still so much to describe...-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: HELL :-) (Was: Re: the anticlassicalist }{ ii: the spectre continues)> On The quote from Martin even continues quite explicitly:>> Strictly, there is only one logic, which, however, can be extended> variously for specic purposes as needed. .95One god, one country, one> logic,' is the stunning phrase of Whitehead.>> Nonsense. This is just a description of HELL! :-)lolYou never did understand why I was posting to sci.logic. :-)In Process and Reality Whitehead had been kind enough to say that mathematicsset a bad example for philosophy. Of course, his discussion of extensiveconnection in later chapters relegated that to a vacuous nonsequitur. But, onemight say that he tried to not...????When professionals in every academic discipline involve their topic withmathematics as a justicationalist tool, people with a sense of the subject mustinvariably suffer. Imagine trying to make sense of inconsistent mathematics, http://plato.stanford.edu/entries/mathematics-inconsistent/ However, specifying a topological space by itsclosed sets is every bit as reasonable as specifying itby its open sets. Yet the logic of closed sets is knownto be paraconsistent, ie. supports inconsistent theories;Naturally while the academic jackasses argue about these matters at faculty tea,they continue to teach nonsense (=inconsistent) to their students. Caveatemptor. It is all too easy when one has refuge in the pathetic retort, But, *I*am not talking about THAT!As an example of the dark side with this issue, let me consider Grothendieck for amoment. Pierre Cartier has a lovely paper about space and symmetry http://modular.fas.harvard.edu/sga/from_grothendieck.pdn months inprison and a ne of 20,000 francs. It seems to methat his denitive break with science dates from thisincident. He withdrew more and more into his owntent. After 1993 he no longer had a postal addressand settled into a hamlet in the Pyrenees. Very fewmanaged to see him there. If I can believe his mostrecent visitors, he is obsessed with the Devil, whomhe sees at work everywhere in the world, destroyingthe divine harmony and replacing 300,000 km/sec by299,887 km/sec as the speed of light!It is terribly easy to relegate this to nonsense--but, after all, we are talkingabout HELL here. :-)There is an embedding theorem in combinatorial topology stating that everyn-dimensional triangulation is isomorphic to a triangulation in 2n+1 dimensions.Currently, there appears to be a group of theoretical physicists advocating atheory embedded in the symmetries of a 26-dimensional Lorentzian lattice. So,here is a little calculation for Grothendieck's Devil,300,000299,887------- 113Using the number 26, we have(26)...(1)...(26) 53 2n+1 2 2-monotonic ordering constants --- 55(55)...(1)...(55) 111 2n+1 2 2-monotonic ordering constants --- 113And, of course, I just made a different post mentioning the logic of apseudocomplemented lattice in which everything becomes true after no more than twoapplications of pseudocomplementation,-----...and as a pseudocomplemented distributive lattice with pseudocomplementa* | 0 if a <> 0 Chains with 0, 1 : a* = | | 1 if a = 0-----Unlike Cartier, I recognize a certain rationality behind the reported fact. Thatis not to say that I concur with the conclusion, however.One wants to immediately say that mitch is engaging in nonsense, trickery, ornumerology. Well, perhaps we should overlook the fact that* INCONSISTENCY SHOULD BE NONSENSE**MATHEMATICS IS FULL OF TRICKS**REDUCING TOPICS TO THE SCIENCE OF NUMBER IS NUMEROLOGY*Regardless, if we are going to accept mathematical principles in any case, weshould not be ignoring the statistical entropy described by Shannon and the factthat there is almost no understanding of analog-to-digital quantization inmultiple dimensions (per Sphere Packings, Lattices and Groups by Conway andSloane). In my opinion, that is what seems to be involved here.Now, I will gladly admit to being confused. There is plenty of evidence of thaton sci.logic in the past year.And, I will gladly admit to talking in circles. Indeed, I have been accused ofthat often enough as well.But, let me share a non-circular observation with everyone. Whereas I thought theappearance of 26 dimensions might have had to do strictly with the ubiquity of theEnglish alphabet in technical literature, I was completely astonished when Irecently opened my Bible on a lark. Turning to the Book of Numbers, the prefacereads---The Book of Numbers derives its name from the account ofthe two censuses of the Hebrew people taken one near thebeginning and the other toward the end of the journey in thedesert (chapters 1 and 26)---Once again, this is not about numerology. It is about the structure onformation. At http://www.research.att.com/~njas/lattices/ANABASIC_11.htmlyou willfind the description of an 11-dimensional lattice for which no subset ofminimal vectors forms a basis. The Gram matrix for this lattice is 60 5 5 5 5 5 -12 -12 -12 -12 -7 5 60 5 5 5 5 -12 -12 -12 -12 -7 5 5 60 5 5 5 -12 -12 -12 -12 -7 5 5 5 60 5 5 -12 -12 -12 -12 -7 5 5 5 5 60 5 -12 -12 -12 -12 -7 5 5 5 5 5 60 -12 -12 -12 -12 -7-12 -12 -12 -12 -12 -12 60 -1 -1 -1 -13-12 -12 -12 -12 -12 -12 -1 60 -1 -1 -13-12 -12 -12 -12 -12 -12 -1 -1 60 -1 -13-12 -12 -12 -12 -12 -12 -1 -1 -1 60 -13 -7 -7 -7 -7 -7 -7 -13 -13 -13 -13 96As can plainly be seen, the number 60 (that is, the base of the sexigesimal numbersystem used by ancient Sumer) lies on the diagonal in every position except thelast. As for the number 96, it plays an essential role in quantum logic. On page5 Jacek Malinowski's paper, http://www.uni.torun.pl/~jacekm/swc1.pdfyou will see mention of the Chinese lantern. This is a six element orthomodularlattice. The description of a quantum consequence operation depends on the crossproduct of this structure with the sixteen standard Boolean switching functions.This is discussed in Protoalgebraic Logics by Janusz Czelakowski, although theproof is omitted.Naturally, this has very little to do with interpreting physics--there are nooperators on a Hilbert space such that PQ-QP=1. But, it might indicate the properinterpretation of quantum logics with respect to information theory--if there wasanyone paying close enough attention.But, like Pavlov's dogs, everyone has been trained to say, *I* don't donumerology.Oops... too late.For those interested in that kind of thing, one might compare the Gram matrixabove with the story about separating the rocks when crossing the Jordan riverinto the Promised Land. But, keep in mind that the mathematical comparison shouldbe the fact that convex deltahedra can have a maximum of 20 sides. A 60-sideddeltahedron is not convex. The story is about discarding information. One cannd the relationship between the sexigesimal number system and the Great PlatonicYear in the work of Joseph Campbell.Anyway, if I apply the same sort of construction as with Grothendieck'srecalculation, I might write,(11)...(1)...(11) 23 2n+1 2 2-monotonic ordering constants --- 25And, coincidentally, Ifind a 25 member listing in Conway and Sloane. What isparticularly interesting is that the endpoints are xed at 0 and 1, as is neededby classical logic. n lattice density 0 0 1 1/2 2 1/(2*surd(3)) 3 1/(4*surd(2)) 4 1/8 5 1/(8*surd(2)) 6 1/(8*surd(3)) 7 1/16 8 1/16 9 1/(16*surd(2))10 1/(16*surd(3))11 1/(18*surd(3))12 1/2713 1/(18*surd(3))14 1/(16*surd(3))15 1/(16*surd(2))16 1/1617 1/1618 1/(8*surd(3))19 1/(8*surd(2))20 1/821 1/(4*surd(2))22 1/(2*surd(3))23 1/224 1Anyone with the slightest grasp of how Lie algebras are applied by generalizationto answer questions in quantum physics should look at the triples for n=(9,10,11)and n=(13,14,15). The graph K_(3,3) is non-orientable, and, the logical analysisof quantum operators by von Neumann and Birkhoff led to Mackey's seventh axiom.That is, the logic of quantum mechanics suggests a framework of innitely manyquestions. I can see it now...Give me 3.Give me 3 more.Give me 3 more.Give me 3 more.ad innitum.I know that it is difcult to understand my point--after all, people talking incircles leave little room for a rational person to get a word in edgewise.Almost everyone *knows* that a sufcient amount of text will permit somenegative (apocalyptic) conclusion under statistical Positivity,Total positivity is a concept of considerable power thatplays an important role in various domains of mathematics,statistics, and mechanics. In mathematics, totally postivefunctions gure prominently (though sometimes indirectly)in problems involving convexity, moment spaces, eigenvaluesof integral operators, and the oscillation properties o¤inear differential equations, as well as in the theory ofapproximations and other areas of real analysis. In statisticsthe theory of total positivity is fundamental to an understandingof statistical decision procedures, and especially in discerninguniformly most powerful tests for hypotheses involving anite set of real parameters. Total positivity is also ofgreat importance in ascertaining optimal policy for inventoryand production processes, in evaluating the reliability ofcoherent systems, in the analysis of diffusion-type stochasticprocesses, and in the study of coupled mechanical systems.one begins to realize that mathematical pictures are easily biased. This seems toresult from picture-thinking and can be expressed formally in terms of theisoperimetric inequality,---The area F and the length L of any plane domain with rectiableboundary satisfy the inequality L^2 - 4(pi)F >=0;the equality sign holds only in the case of a circle---At least the physicists seem to be concerned with one particular circle. Theequation for the ne structure constant, Alpha, is of the form, e^2 4(pi)Alpha = --------------------- (epsilon_0)(h-bar)(c)So, unlike Grothendieck, I have no particular concern about the speed of lightchanging. But, circles are convex domains and it is the mathematics of convexitythat is ubiquitous.The more I investigate the history of this subject, the more clear it is thatthese issues, mathematics has the soma effect a feel-good generation desires.But, someone has to have made a mistake unless there is no such thing as reality.My experience with closed physical systems is that there are conservation laws.:-)mitch === Subject: JSH: Question of intentI've been thinking about formalizing the argument with which I prove aproblem with the ring of algebraic integers, and ran into a problem.I'd envisioned a proof along the lines of, given algebraic integerfunctions f_1(x), and f_2(x), where f_1(0)=f_2(0) = 0, and algebraicinteger function P(x), also a primitive polynomial, where(f_1(x) + 7)(f_2(x) + 1) = 7P(x)it must be true that f_2(x) + 1 is coprime in general to 7 implyingthat f_1(x) has 7 as a factor in general, but as it does not in thering of algebraic integers, there is a problem with the traditionalunderstanding of that ring.The only problem is that thinking of it that way I realized that it'snot true, since you *can* have algebraic integer functions that neverequal 0, which are themselves factors of 7.For instance, you can just take the roots ofy^2 + (b+8)y + 7.Now I posted somewhat on this subject earlier as the issue here reallyis the ability of someone to come along and use certain functions tomultiply times any factorization and get something interesting.However, that requires intent, since there are an innity of suchfunctions available, even to factor 7 into two ways, so how do youchoose?A human being can pick functions for any number of reasons, and itwouldn't surprise if they picked something easy, like the roots ofy^2 + (b+8)y + 7.So what's different with my argument? The answer is that multiplyingby a function means you have multiplied by that function, and hidingthat fact requires more intent.Like in my earlier post, if I have w_1(x)(f_1(x) + 1), then you havew_1(x) f_1(x) + w_1(x)and to hide that fact and appear to have a free contant term requireswrapping things up quite deliberately, like((w_1(x)(f_1(x) + 1) - 1) + 1and using say, a_1(x) = (w_1(x)(f_1(x) + 1) - 1)to geta_1(x) + 1so that it *looks* like there's a free constant term of 1.Now it's easy to demonstrate that, but regardless of how it was made,a_1(x) *is* still an algebraic integer function!The issue here then is that you can have functions without trueconstant terms, while I rely onfinding constant terms.However, it takes intent, as there are an innity of such examples,and if a human being isn't trying to hide functions by wrapping themup like I showed above, then you can simply separate off any suchfactor like w_1(x).I'm still thinking about how to go about saying that formally:Given algebraic integer functions f_1(x), and f_2(x), wheref_1(0)=f_2(0) = 0, and algebraic integer function P(x), also aprimitive polynomial, where(f_1(x) + 7)(f_2(x) + 1) = 7P(x)where 7 is a truly a constant term of f_1(x) + 7, and not a made upone for effect? How do you handle human intent mathematically?James Harris === Subject: Re: JSH: Question of intent> How do you handle human intent mathematically?Easy.IF .95mathematics is posted by JSH'THEN .95intent is to aggrandize self and afrm own magnicence'ELSE .95intent is irrelevant'> James The Magnicent, W.O.O.O Harris--There are two things you must never attempt to prove: the unprovable --and the obvious.--Democracy: The triumph of popularity over principle.--http://www.crbond.com === Subject: Re: JSH: Question of intentX-DMCA-Notications: http://www.giganews.com/info/dmca.html>I've been thinking about formalizing the argument with which I prove a>problem with the ring of algebraic integers, and ran into a problem.Guffaw! Of course you did. It's probably similar to the problemsI run into every time I try to formalize my proof that the Earthis ¤at.>[...] How do you handle human intent mathematically?You don't - mathematical proofs do not involve any such notion.>James Harris************************David C. Ullrich === Subject: Re: Question of intent (PG13)James Harris> I've been thinking about formalizing the argument with which I prove a> problem with the ring of algebraic integers, and ran into a problem....Meaning that another absurd claim of yours was trivially refuted.I know lots of self-interested liars, Harris, but I fail to see who it isyou hope to deceive with this of yours -- page after page about ain' quadratic polynomial. Don't you get tired of making such an ass ofyourself? You never succeed in deceiving anyone, and you prove nothingexcept your own ignorance, over and over. === Subject: Re: Difference between polynomial and eld arithmetic!!Thanx for your explanation.. but I really don't understand thedifference in calling them Polynomial arithemtic and eldarithemtic.. as, for example, when i do a polynomial addition whosecoefcients are eld elements..say in GF(2^m) I am basically addingthe eld elements ..(adding coefcients for that particularpower)thus making it eld arithemtic.. similar case formultiplication....so what I don't understand is how come it ispolynomial arithmetic and is more complex.. compared to eldarithmetic???i hope i clearly explained my question. any difference between eld>arithmetic and polynomial arithmetic.>>Any help would be greatly appreciated.>> make more sense to ask> whether there is any connection between the two, rather than what is> the difference between them. Many elds are of the form F(a), where F is some more basic eld.> Typically, F is either a nite eld F_p of integers mod p, or F is> the eld of rational numbers, and you assume that you can already do> arithmetic in F. The element a could be either transcendental or algebraic over F.> In the rst case, F(a) is isomorphic to the eld of rational functions> over F, so arithmetic in F(a) can be carried out using polynomial> arithmetic. If a is algebraic over F, then it satises a minimal polynomial f(a) = 0,> for some polynomial f, and then arithmetic in F(a) can be carried out> using polynomial arithmetic modulo f. But for reasonably small nite elds, there are other methods of doing> arithmetic, which do not involve polynomial arithmetic, which can be more> efcient. One way is to choose a primitive element b of the eld, and> represent nonzero elements x by the integer n, where x = b^n.> Then multiplication is very fast, and addition can be carried out using> a stored pre-computed table of Zech logarithms l(n), dened by> b^n + 1 = b^{l(n)}. Derek Holt. === Subject: Re: PDE Max-Min Principle (Help?)Mohan Pawar question really about math...>> Prove that if u(x,t) <= v(x,t) for x=0, for x=l (lower-case L), for>> t=0, then u<=v for all (x,t) in 0<=x<=l, 0<=t<=oo. Given> u(0,0) <= v(0,0)> u(L,0) <= v(L,0)I think it is saying:Givenu(0,t) <= v(0,t)u(L,t) <= v(L,t)u(x,0) <= v(x,0)> Prove that> For certian class of PDEs , u(x,t) <= v(x,t) for all (x,t) in> 0<=x<=L, 0<=t<=oo Is this correct interpretation of your question? I am missing> something. Mohan Pawar> - Tim-- Timothy M. BrauchGraduate StudentDepartment of MathematicsWake Forest University === Subject: Re: PDE Max-Min Principle (Help?)The World Wide Wade u(x,t) <= v(x,t) for x=0, for x=l (lower-case L), for>> t=0, then u<=v for all (x,t) in 0<=x<=l, 0<=t<=oo. Ridiculous as it stands. Please include all hypotheses. (Also, what> does t = oo mean here?)> Sorry, at the beginning of the problem set, we were told that u and v are are solutions to the diffusion (heat) equation u_t = k*u_xx.There is a hint that says this is proving the Comparison Principle using the Maximum-Minumum Principle.Also, that last inequality should read 0<=t >> t=0, then u<=v for all (x,t) in 0<=x<=l, 0<=t<=oo.>> Ridiculous as it stands. Please include all hypotheses. (Also, what> does t = oo mean here?)> Sorry, at the beginning of the problem set, we were told that u and v> are are solutions to the diffusion (heat) equation u_t = k*u_xx. There is a hint that says this is proving the Comparison Principle> using the Maximum-Minumum Principle.can you apply the Maximum-Minumum Principle. to w=u-v ? which PDE and boundaryconditions does w fulll?hthklaus Also, that last inequality should read 0<=t innity. Like I said, I'm not looking for the answer, just a way to start the> beast. Most other problems in this set were proving properties of the> diffusion equation using change of variables and the chain rule. That> does not seem to work here. - Tim --> Timothy M. Brauch> Graduate Student> Department of Mathematics> Wake Forest University === Subject: Re: PDE Max-Min Principle (Help?)The original post has some data missing and I am hoping that the hint belowhelps.Assume PDE u_t = u_xx for t >0, 0 < x < LNote that the given IC impliesIC => u(x,0) - v(x,0) = w(x) for 0 =< x =< LNow the given BCs also implyBC1 => u(0,t) - v(0,t) = k1, k1 > 0, t >0BC2 => u(L,t) - v(L,t) = k2, k2 > 0, t >0Hint:Begin withu(x,t) - v(x,t) = w(x) => v(x,t) = u(x,t) - w(x)Convert given original IBV problem in u into a new IBV problem in v. Anintermediate simple BVP is created in the process.If I didn't mess up the simple BVP should look likew(x)=0w(0)=k1w(L)=k2solve this for w(x). Tie loose ends and make the argument leading tou(x,t) - v(x,t) > w(x) for t >= 0, 0 =< x =< L------------------Mohan Pawar------------------klaus hoffmann that if u(x,t) <= v(x,t) for x=0, for x=l (lower-case L), for> >> t=0, then u<=v for all (x,t) in 0<=x<=l, 0<=t<=oo.>> > Ridiculous as it stands. Please include all hypotheses. (Also, what> does t = oo mean here?)>>> Sorry, at the beginning of the problem set, we were told that u and v> are are solutions to the diffusion (heat) equation u_t = k*u_xx.>> There is a hint that says this is proving the Comparison Principle> using the Maximum-Minumum Principle.> can you apply the Maximum-Minumum Principle. to w=u-v ? which PDE andboundary> conditions does w fulll?>> hth> klaus>>> Also, that last inequality should read 0<=t innity.>> Like I said, I'm not looking for the answer, just a way to start the> beast. Most other problems in this set were proving properties of the> diffusion equation using change of variables and the chain rule. That> does not seem to work here.>> - Tim>> --> Timothy M. Brauch> Graduate Student> Department of Mathematics> Wake Forest University === Subject: Re: How tofind near integer values of n*a and n*b?israel@math.ubc.ca (Robert B. Israel) efcient way to solve the following problem:|> Given a,b,eps>0 nd all positive nwithin eps>|> of being integer.|> For example, let a=sqrt(2), b=sqrt(3) and eps=10^-k. I've compiled a>table of>|> n that work for various small values of k. Is it complete? >>Given any m real numbers x_1,...,x_m, there exist innitely many positive>integers n such that n x_j are all within n^(-1/m) of integers. But I don't>think there's a lot more known on this topic. > I'm curious if there might be some *reason* to think the following is true:Consider the set X=X(x_1,x_2)={n:n*x_1 and n*x_2 are within n^(-1/2) ontegers}. Is there a constant k such that for each n in X there exist n_i inX and integers a_i>0 with n=sum(a_i*n_i) and sum(a_i)<=k?Unless I have made an error, if x_1=sqrt(2) and x_2=sqrt(3) and n<=1580818405then k=10 always works and k=2 usually works. Some examples of this (usingRI's data) are the following:>> d, n, eps> 5, 41, 0.017243942841=22+19> 6, 1463, 0.00966852671463=1422+41> 7, 4109, 0.00352779114109=2646+1463> 8, 20586, 0.002075387020586=16477+4109> 9, 326491, 0.0002139702326491=171484+155007> 11, 2151016, 0.00010642382151016=1824525+326491> 13, 78411940, 0.00004235278411940=51448791+26963149> 14, 447810523, 0.0000111850447810523=237386836+210423687> 15, 1580818405, 0.00000546921580818405=1133007882+447810523> 16, 10011132893, 0.000001018710011132893=8430314488+1580818405So it seems as though many elements of X(sqrt(2),sqrt(3)) can be written as asimple sum of two other members of X (i.e. k=2, often). However, if n=134421 then n=6*20586+2*4109+2646+41, so k>=10. Is there anyreason (otwt) to believe that k=10 might work for all n in X?Rich === Subject: Re: Bound of a sum>>I admit I am no math genius, but I need tofind some way to bound>>k-1 n> >>sum sum 2/(j-i+1)>>i=1 j=k+1>>Any upper bound that is some constant by n is OK.>Write the sum as >S = sum_{r=3}^n f(r,k)/r >where f(r,k) = min(k-1,n-r+1) - max(0,k-r+1).> Oops, somehow I lost the 2. So my bound would be 2n.> Robert Israel ==Let k-1 n S(n,k):= sum sum 2/(j-i+1) , where 1< k < n . i=1 j=k+1In the following a,b,r,s,n denote positive integers, and h(n)=1+1/2 +1/3+ ....+1/n , g_r(a) =h(r*a) - h(r)J.Lambek and L.Moser, see ,,Rational analogues of the logarithm function,Math.Gaz. 40 (1956), 5-7, have established the inequalities a/(a+b) =< h(a+b) - h(b) < a/b , 0=< g_{r+1}(a) -g_r(a) < 1/r -1/(r+1) ,(1) 0=< g_s(a)-g_r(a) < 1/r -1/s if r> statement that e+pi and e*pi remembered>correctly - or they lack someting :-)Let u=e+pi, and v=e*pi.Also, u and v are both positive, and e < pi.Let uu = u/2.v = (uu+x)*(uu-x) = uu^2 - x^2.Hence, x = v - uu^2.And e = uu-x, pi = uu+x.They *had better* not be both algebraic, or e and pi would be too!John Savardhttp://home.ecn.ab.ca/~jsavard/index.html === Subject: Re: 21:37:11 -0500, Michael N. is the origin of space and time?>> Space and time is the 4D fabric within which all life>> has evolved.>> Wrong. It is in fact the 8th dimentional time-space fabric.>> See .95The adventurures of Buckaroo Banzai across the 8th dimension'.>> Do your homework, kid!>>Uh, I think it is you who needs to do the homeowork. Everyone knows there>are exactly FIVE dimensions. Every hear about a little something called>'Twilight Zone' (aka the fth dimension) !?!?! I bet you feel pretty dumb>right about now.Actually, we're not sure. There may be 10 or 11 dimensions, dependingon whether you go with superstrings or supergravity. But there's a newtheory that says the extra dimensions aren't curled up into littleballs or toruses after all, and the Universe is held in four of thosedimensions through a different mechanism...On the other hand, I remember once from an old Flash comic book wherethe Flash and Kid Flash visited a world with 24 dimensions, inhabitedby tall grey beings who looked very three-dimensionally humanoid...John Savardhttp://home.ecn.ab.ca/~jsavard/index.html === Subject: Re: is the origin of space and time?Where and when could space and time have originated, if there was nospace and time before they originated?John Savardhttp://home.ecn.ab.ca/~jsavard/index.html === Subject: Re: +0100, the role of innity in math:The role of completed innity is limited to stuff like axiomatic settheory, but incomplete innity pervades mathematics.>How is it dened?>>Why is it needed?>>At what precition does math work?If math were limited to any set precision, it would be merecomputation, and if a higher precision were needed, then we would haveto work out math all over again.That's why innity is needed in math, so we get it right the rsttime.John Savardhttp://home.ecn.ab.ca/~jsavard/index.html === Subject: Re: The role of innity in mathjsavard@ecn.aSBLOKb.caNADA.invalid limited to stuff like axiomatic set> theory, but incomplete innity pervades mathematics. What's incomplete about the innity of the real numbers? === Subject: Re: Mathcad Upgrade QuestionMathcad 11 is worth the upgrade but I have found that it doesn't workreliably on WIN98. I upgraded to WINNT and it works ne. I also hatec-dilla, but it should do anything bad to your system unless you have somesoftware that scans for trojans and stealth programs. I would rather havea USB dongle.Peter NachtweyRobert Wynne 2001i this weekend. After> installition I noticed that c-dilla had also been introduced to myregistry.> Google c-dilla tofind out what this program does. Anyhow I have spent 2> days rebuilding my hard drive because of the damage that Mathcad did.> Steven in> I am thinking of upgrading from an old version of Mathcad (Version 7)> to the most recent. But past experience with upgrades has taught me> to be a bit wary, so 2 questions:> >> 1. Did Mathsoft do anything to screw up the product, in terms of> usability or features, since I last purchased it (back in 1997)?>> 2. Does the latest product come with any kind of registration> feature, like Mathematica has, that locks your software into one> computer, and possibly locks you out of the software if you upgrade> your hardware? (I respect the rights of companies to make money off> their software, but I'm a rm believer that the only fair deal is> one-user/one-app. If I have three computers -- and I do -- I should> not have any worries or complications with loading the same software> package on all three of them.)>> Standard Anti¤ame Disclaimer: Please don't ¤ame me. I may actually> *be* an idiot, but even idiots have feelings.>> === Subject: Re: Mathcad Upgrade QuestionYes spybot caught on to it. Besides I don't like folks putting stuff on mycomputer without telling me rst.Neither Mathematica nor Matlab has any problems with the way I use mycomputer. Does Mathcad 11 usec-dilla to keep track of what your doing? Or did the upgrade but I have found that it doesn't work> reliably on WIN98. I upgraded to WINNT and it works ne. I also hate> c-dilla, but it should do anything bad to your system unless you have some> software that scans for trojans and stealth programs. I would ratherhave> a USB dongle.>> Peter Nachtwey>> Don't use mathcad. I installed version 2001i this weekend. After> installition I noticed that c-dilla had also been introduced to my> registry.> Google c-dilla tofind out what this program does. Anyhow I have spent 2> days rebuilding my hard drive because of the damage that Mathcad did.> Steven O. > I am thinking of upgrading from an old version of Mathcad (Version 7)> to the most recent. But past experience with upgrades has taught me> to be a bit wary, so 2 questions:> >> 1. Did Mathsoft do anything to screw up the product, in terms of> usability or features, since I last purchased it (back in 1997)?>> 2. Does the latest product come with any kind of registration> feature, like Mathematica has, that locks your software into one> computer, and possibly locks you out of the software if you upgrade> your hardware? (I respect the rights of companies to make money off> their software, but I'm a rm believer that the only fair deal is> one-user/one-app. If I have three computers -- and I do -- I should> not have any worries or complications with loading the same software> package on replies.>> Steve O.>> Standard Anti¤ame Disclaimer: Please don't ¤ame me. I may actually> *be* an idiot, but even idiots have feelings.>> === Subject: Re: Mathcad Upgrade QuestionYou may be coming up against the old saying If it isn't broken, don't xit!. I have MathCad 2000 professional, which works very well and haveresisted the UK seller's efforts to get me to do several upgrades. It soundsas though that was the right decision.I also have Delphi 3, 5 and 7, Personal, on my PC. They all work and 5 wasslightly better than 3 but 7 seems less good than 5. I suspect a lot ofupgrades are more trouble than they are worth.Robert Wynne on to it. Besides I don't like folks putting stuff onmy> computer without telling me rst.> Neither Mathematica nor Matlab has any problems with the way I use my> computer. Does Mathcad 11 use> c-dilla to keep track of what your doing? Or worth the upgrade but I have found that it doesn't work> reliably on WIN98. I upgraded to WINNT and it works ne. I also hate> c-dilla, but it should do anything bad to your system unless you havesome> software that scans for trojans and stealth programs. I would rather> have> a USB dongle.> >> Peter Nachtwey>> Robert Wynne mathcad. I installed version 2001i this weekend. After> installition I noticed that c-dilla had also been introduced to my> registry.> Google c-dilla tofind out what this program does. Anyhow I have spent2> days rebuilding my hard drive because of the damage that Mathcad did.> Steven in> I am thinking of upgrading from an old version of Mathcad (Version7)> to the most recent. But past experience with upgrades has taught me> to be a bit wary, so 2 questions:>> 1. Did Mathsoft do anything to screw up the product, in terms of> usability or features, since I last purchased it (back in 1997)?>> > 2. Does the latest product come with any kind of registration> feature, like Mathematica has, that locks your software into one> computer, and possibly locks you out of the software if you upgrade> your hardware? (I respect the rights of companies to make money off> their software, but I'm a rm believer that the only fair deal is> > one-user/one-app. If I have three computers -- and I do -- I should> not have any worries or complications with loading the same software> package on all three of >> Steve O.>> Standard Anti¤ame Disclaimer: Please don't ¤ame me. I mayactually> *be* an idiot, but even idiots have feelings.>>>> === Subject: 1 to 1 correspondenceHow would I show a 1 to 1 correspondence between (0,1) and [0,1] ????? === Subject: Re: 1 to 1 correspondence> How would I show a 1 to 1 correspondence between (0,1) and [0,1] ?????if you just need to show that (0,1) and [0,1] have the samecardinality (i.e. just the existence of the 1 to 1 correspondance) youmay do the following:1- consider the half-circle, of radius 1 and center P, tangent to thereal line. This half circles represents the interval (0,1) (0 on oneend, 1 on the other). draw a line starting from P and intersecting thereal line. This a geometrically constructed bijection between (0,1)and R.2- Use the Schroder-Bernstein theorem: a) (0,1) in [0,1] in R b) R and (0,1) are equivalent (by 1-)therefore all three sets are equivalent ([0,1], (0,1) and R). === Subject: Re: 1 to 1 correspondence>How would I show a 1 to 1 correspondence between (0,1) and [0,1] ?????Choose any sequence of unique reals a_n from (0, 1). Letf: [0,1] -> (0,1)be dened as0 |--> a_11 |--> a_2a_n |--> a_(n+2)a |--> a, when a not in a_nThen f is a bijection.-- I'm not interested in mathematics that might have anythingto do with reality. -- Russell Easterly, in sci.math === Subject: Re: 1 to 1 correspondence> How would I show a 1 to 1 correspondence between (0,1) and [0,1] ????? One way is to dene f:[0,1] -> (0,1) such that f(0) = 1/2,f(1) = 1/4,f(1/2^n) = 1/2^(n+2), for all positive integers n,otherwise f(x) = x.The above is bijective, but not order preserving. Order preserving and bijective are mutually exclusive properties for mappings between any closed interval of reals and any open interval of reals. === Subject: Re: 1 to 1 correspondenceVirgil to 1 correspondence between (0,1) and [0,1] ?????>> One way is to dene f:[0,1] -> (0,1) such that> f(0) = 1/2,> f(1) = 1/4,> f(1/2^n) = 1/2^(n+2), for all positive integers n,> otherwise f(x) = x.>> The above is bijective, but not order preserving.>> Order preserving and bijective are mutually exclusive properties for> mappings between any closed interval of reals and any open interval of> reals.Ok I see this. === Subject: Re: 1 to 1 correspondence> How would I show a 1 to 1 correspondence between (0,1) and [0,1] ?????Hint: How would you show a 1 to 1 correspondence between{1,1/2,1/3,1/4,...} and {1/2,1/3,1/4,...}?-- Daniel W. Johnsonpanoptes@iquest.nethttp://members.iquest.net/~panoptes/ 039 53 36 N / 086 11 55 W === Subject: The infamous K-man V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}Hi Peter , nnrp1.ozemail.com.au!53ab2750 .You wouldn't be the infamous K-man by any chance, would you ?Sloppy, sloppy. === Subject: Re: The infamous K-man ?> Hi Peter ,> > nnrp1.ozemail.com.au!53ab2750 . > You wouldn't be the infamous K-man by any chance,> would you ? Sloppy, sloppy.Jeff,Be from ozemail.au (Australia).Double-A === Subject: Crikey mate V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}Hi Double-A, You from ozemail.au ( Australia ) . Crikey mate ! Maybe that is him then.I think that's k-man's profession. === Subject: V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}Oops, I called ozemail.com.au!53ab2750 , an anonymous server ... It's not.So what does the 53ab2750 mean ?It seems to be some kind of a control code. === Subject: . 53ab2750 is an anonymous user V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}I asked, I think it means that a proxy client is being used. ( i.e. The poster is being kept anonymous )Normally that number would identify the user. === Subject: Re: . 53ab2750 is an anonymous Jeff Relf: >I asked, >I think it means that a proxy client is being used. > ( i.e. The poster is being kept anonymous ) > >Normally that number would identify the user. No, it wouldn't. Go look up the rfc for the nntp protocol. The pathprior to arriving on the news server on which you are reading the === Subject: Re: . 53ab2750 is an anonymous user V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}Hi Bilge, You mistakenly thought, No, it wouldn't. Go look up the rfc for the nntp protocol. The path line identies the news servers through which I know for a fact that a number like that I sometimes score on it, it works perfectly.For example it identies one exact Earthlink user. take a look at Ha Ha Hanson's headers, you would always know that it was him, and only him.53ab2750 is an anonymous or unauthenticated and anonymous posts ) . === Subject: Re: . 53ab2750 is an Jeff Relf: >Hi Bilge, >You mistakenly thought, > No, it wouldn't. > Go look up the rfc for the nntp protocol. > The path line identies the news servers through which >I know for a fact that a number like that > I sometimes score on it, it works perfectly. No, you don'y know that for a fact, for the same reason you don't knowanything else - you never look up the references. To wit, RFC 1036 says:2.1.6. Path This line shows the path the message took to reach the current system. When a system forwards the message, it should add its own name to the list of systems in the Path line. The names may be separated by any punctuation character or characters (except . which is considered part of the hostname). and Normally, the rightmost name will be the name of the originating system. However, it is also permissible to include an extra entry on the right, which is the name of the sender. This is for upward compatibility with older systems. The Path line is not used for replies, and should not be taken as a mailing address. It is intended to show the route the message traveled to reach the local host. There are several uses for this information. One is to monitor USENET routing for performance... >For example it identies one exact Earthlink user. > take a look at Ha Ha Hanson's headers, > you would always know that it was him, and only him. Only because earthlink _chooses_ to add that as an optional eldfor it's own reasons. It has nothing to do with any requirementto do so as rfc 1036 makes clear. As usual, you make invalid assumptionsand draw unwarranted conclusions. Proof by example dies not constitutea proof. >53ab2750 is an anonymous or unauthenticated user. jeff relf is an anencephalic or brainless poster. === Subject: Re: . 53ab2750 is an anonymous Relf:>Hi Bilge, > You mistakenly thought,> I know for a fact that a number like that > I sometimes score on it, it works perfectly.> For example it identies one exact Earthlink user.> take a look at Ha Ha Hanson's headers, > > you would always know that it was him, and only him.>[Bilge]> jeff relf is an anencephalic or brainless poster.>AHhahahahaha.......ahahahaha...AHAHAHAHHAA......Well, Bilge, I don't know about your evaluation of Jeff,but I must thank Jeff dearly that he takes such a deep andabiding interest in my posted grand wisdoms and goes tothe extreme length to verify and make sure that it is indeedfrom me, hanson@quick.net = !ed99b2be .........AHAHA....HAHAHA......ahahahahaha......AHAHAHHAHAHA... ...That's what I call readership loyalty, Bilge!Jeff, you get three attaboys for this!AHahhahahaha....ahahahanson === Subject: Re: . 53ab2750 is an anonymous user .hanson > You mistakenly thought,> I know for a fact that a number like that > I sometimes score on it, it works perfectly.> For example it identies one exact Earthlink user.> take a look at Ha Ha Hanson's headers, > you would always know that it was him, and only him.>> [Bilge]> jeff relf is an anencephalic or brainless poster.>> AHhahahahaha.......ahahahaha...AHAHAHAHHAA......> Well, Bilge, I don't know about your evaluation of Jeff,> but I must thank Jeff dearly that he takes such a deep and> abiding interest in my posted grand wisdoms and goes to> the extreme length to verify and make sure that it is indeed> from me, hanson@quick.net = !ed99b2be .........AHAHA....> HAHAHA......ahahahahaha......AHAHAHHAHAHA......> That's what I call readership loyalty, Bilge!> Jeff, you get three attaboys for this!> AHahhahahaha....ahahahansonIt sure doesn't take much to make you laugh> === Subject: Re: . 53ab2750 is an Jeff Relf:>Hi Bilge, > You mistakenly thought,> > I know for a fact that a number like that > I sometimes score on it, it works perfectly.> For example it identies one exact Earthlink user.> take a look at Ha Ha Hanson's headers, > you would always know that it was him, and only him.>> [Bilge]> jeff relf is an anencephalic or brainless poster.>> AHhahahahaha.......ahahahaha...AHAHAHAHHAA......> Well, Bilge, I don't know about your evaluation of Jeff,> but I must thank Jeff dearly that he takes such a deep and> abiding interest in my posted grand wisdoms and goes to> the extreme length to verify and make sure that it is indeed> from me, hanson@quick.net = !ed99b2be .........AHAHA....> HAHAHA......ahahahahaha......AHAHAHHAHAHA......> That's what I call readership loyalty, Bilge!> Jeff, you get three attaboys for this!> AHahhahahaha....ahahahanson It sure doesn't take much to make you laugh> >AHahahahaha....AHAHAhahahaha...ahahaha....Your are so right, Peter. It does not take much to makeme smile, laugh, roar, ROTL or ROTFLMAO...ahahahaha..That's why you too get three attaboys for your reply !Life's a bowl of cherries, pits and nuts and all....ahahahahaha.......ahahahahanson === Subject: Re: 53ab2750 ?> Oops, I called ozemail.com.au!53ab2750 ,> an anonymous server ... It's not. So what does the 53ab2750 mean ? It seems to be some kind of a control code.I just guessing now...Could it be the IP address written in hexadecimal, i.e. 83.171.39.80?-Michael. V|9[5IY]/OB15+}/e : m!6.qw'Kzn@$#CJQl/UvR,&G?sNO{#LEEnS3lQRnT#Ql#' 3ySQ80}u7Q<`+B@; Y;81AnK'_PD^fm.3T/<-i~YdZ%Q}b?:-]{Lr#s6.N,r(}Hi Michael Jrgensen, You ventured, Could it be the IP address ,A number like 53ab2750 would normally identify the poster, but 53ab2750 seems to mean: An anonymous poster . === Subject: Re: wanted: sha1:mfuAXgK49IwzXanM+hg4/lqFWMo=see.address@post.sig these false proofs.> I'm surprised everybody here missed this unique opportunity of killing two> birds with one stone.>> Starting with a rock solid result from harrissian fundamental tautology> space theory and developping at an elementary level, here is a crystal clear> proof of a core error in mathematics.> (0) 1 = 1>> (1) 1 = sqrt( 1 )>> (2) 1 = sqrt[ (-1)^2 ]>> (3) 1 = sqrt[ (-1) * (-1) ]>> (4) 1 = sqrt( -1 ) * sqrt( -1 )>> (5) 1 = i * i>> (6) 1 = -1> Please note that some nitpickers might argue that sqrt being such an> ambiguous and lunatic operator, the odds of sqrt(-1) evaluating to (i) the> rst time and (-i) the second time (or vice-versa) are not completely> negligeable.You've missed the linguistic turn this morning that explains thingsbetter now. There are two numbers that, when squared, yield 1. Forthe square root operator to *always* return the positive of these twowould require human *intent*. Mathematics always works for a reason,but humans choose arbitrarily and so while they can form intent, QueenMathematics cannot.Therefore, sometimes the square root operator must sometimes choosethe negative root.-- Jesse F. Hughes[Mathematical] society has evolved far enough away from mainstreamsociety that it has become rogue, and now is willing to push its needsagainst that of the majority. -- James S. Harris === Subject: New crypto algorithmDedicated to the Faculty of Mechanics and Mathematics of Belarusian StateUniversityThis message denes new symmetric cryptoalgorithm and contains animplementation that can be used for practical testing.The cryptoalgorithm has the following advantages: 1. Keys of arbitrary length are allowed. 2. The cryptoalgorithm is extremely easy to understand and implement. 3. The cryptoalgorithm is strong (not proved), open and free. I am theoriginator of this cryptoalgorithm and I tell you: use it for free.The cryptoalgorithm is based on the process of conversion from one numericsystem to another: a number is converted to another numeric system, thedigits are permuted and the result is converted back to the original numericsystem.Description of the cryptoalgorithm:- Plain text to encode is (long) unsigned integer number. Let's denote it byA.- Similarly, key is unsigned integer number B. 0. Plain text is compressed in order to transform it into a relatively random(i.e. uncompressible) sequence of bytes using some compression algorithm. 1. A is split into a sequence of remainders of division by B. 2. The sequence of remainders is permuted. B's value denes the permutation. 3. The permuted sequence is converted to number A2.- A2 is the encoded text. The following Java program is created for practical testing. It is a completeimplementation of the cryptoalgorithm (without compression phase).-------------------------------- A.java --------------------------------import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.math.BigInteger;import java.util.LinkedList;import java.util.ListIterator;public class A{ public static void main(String[] args) throws Exception { if (args.length!=4) badArgs(); String scmd=args[0]; String skey=args[1]; String sin=args[2]; String sout=args[3]; if ( !(e.equals(scmd) || d.equals(scmd)) ) badArgs(); boolean encrypt=e.equals(scmd); BigInteger b=new BigInteger(1, readFile(skey, 0)); if (encrypt) { byte[] adata=readFile(sin, 1); // append positive most signicant (random) byte for (int i=1; i=0; i--) { a=a.multiply(b); a=a.add(rems[i]); } return a; } public static BigInteger[] permute(BigInteger[] rems, BigInteger b, boolean inverse) { int len=rems.length; BigInteger[] ret=new BigInteger[len]; int pos[]=createPermutation(len, b, inverse); for (int i=0; i=1; div--) { BigInteger bdiv=new BigInteger(+div); if (div==len) // always move bdiv=bdiv.subtract(BigInteger.ONE); // most signicant remainder if (b2.compareTo(bdiv)<0) b2=b; // restart from b BigInteger[] qr=b2.divideAndRemainder(bdiv); b2=qr[0]; int rem=qr[1].intValue(); ListIterator lit=lst.listIterator(rem); ret[div-1]=((Integer)lit.next()).intValue(); lit.remove(); } if (inverse) { int[] ret2=new int[len]; for (int i=0; i D.McAnally@i'm_a_gnu.uq.net.au specicity, it is a>>wff of the FOL of set theory which is (roughly speaking) stipulated>>true, and can thus be used in deductions. If you decide that you>>don't like the axiom of choice, you can choose to not work with FO>>languages which include it. But even then, it's hard to deny it's use>>in axiom systems which _do_ use it. (Since, by construction, you're>>setting up a conditional... If the axiom of choice is true, and>>...blah..., then ...blah'...)>>In any case, there is nothing to prove.>As I stated above, the Metamath formulation of the Axiom of Choice is >effectively the statement that given any set x, there exists a set y > >such that for all nonempty elements w of x, w n (Us) has exactly one >element, where s = {t in y : w in t}. This is not amongst the >formulations of the Axiom of Choice of which I was previously aware.>The question of the equivalence of the Metamath formulation with the>more standard versions under ZF naturally arises, as such an equivalence >is necessary if the Metamath set theoretic axioms are to be taken as >axioms of ZFC. Also, the motivation behind proving the equivalence of the Metamath > formulation of the Axiom of Choice and more standard formulations> is the same as the motivation behind proving the equivalence of the > Axiom of Choice and Zorn's Lemma, and the equivalence of the Axiom > of Choice and the Well-Ordering Theorem. I presume that you have > seen the proofs of these last two mentioned equivalences, Acid Pooh.> Heh. Since you appear to be goading me into replying, and I'm asucker for this sort of thing, here goes: I was not aware thatMetamath was a website. Nor was I aware that they had a differentversion of the axiom of choice. I assumed (obviously incorrectly)that you meant metamath to refer to Set Theory, or some suchmetamathematical study. Now, in this context, my response doesn'tseem so inappropriate, does it? In particular, it shouldn't seem sopatronizing, since, as I parsed your question, it is a question abeginner should ask. So, why decide to patronize me?'cid .95oohPS. Chill out. === Subject: Re: Metamath Axiom of Choice>> D.McAnally@i'm_a_gnu.uq.net.au formulation of the Axiom of Choice is >>effectively the statement that given any set x, there exists a set y >>such that for all nonempty elements w of x, w n (Us) has exactly one >>element, where s = {t in y : w in t}. As stated, it is false. Add the elements of x are disjointand it is one of the standard forms.To see that it is false as stated, let x have three elements, {1, 2}, {1, 3}, {2, 3}. Any set intersecting all of these inat least one element has to contain both elements of one.-- 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 Universityhrubin@stat.purdue.edu Phone: (765)494-6054 FAX: (765)494-0558 === Subject: Re: Metamath Axiom ...................>As I stated above, the Metamath formulation of the Axiom of Choice is >effectively the statement that given any set x, there exists a set y >such that for all nonempty elements w of x, w n (Us) has exactly one >element, where s = {t in y : w in t}. >As stated, it is false. Add the elements of x are disjoint>and it is one of the standard forms.>To see that it is false as stated, let x have three elements, >{1, 2}, {1, 3}, {2, 3}. Any set intersecting all of these in>at least one element has to contain both elements of one.But in the statement above, s is explicitly t}), so the claim is not the existence of a single set with one element in commonwith every nonempty element.If we take x = {{1,2},{1,3},{2,3}}, then take y = {{{1,2},1},{{1,3},1},{{2,3},2}}.For the element w = {1,2}, s = {t in y : w in t} = {{{1,2},1}}, so that Us = {{1,2},1}, and so w n (Us) = {1} has exactly one element.For the element w = {1,3}, s = {t in y : w in t} = {{{1,3},1}},so that Us = {{1,3},1}, and so w n (Us) = {1} has exactly oneelement.For the element w = {2,3}, s = {t in y : w in t} = {{{2,3},2}},so that Us = {{2,3},2}, and so w n (Us) = {2} has exactly oneelement.David McAnally At the moment, they (the Time Lords) are far from being all-powerful. That's why it's been left up to me and me and me. quote by: Patrick Troughton in The Three Doctors------- === Subject: Re: Metamath Axiom of Choice sha1:7KR/2dC3CE+vTR0AUl1MPgWQp3U=poohonlsd@yahoo.com (Acid replying, and I'm a> sucker for this sort of thing, here goes: I was not aware that> Metamath was a website. Nor was I aware that they had a different> version of the axiom of choice. I assumed (obviously incorrectly)> that you meant metamath to refer to Set Theory, or some such> metamathematical study. Now, in this context, my response doesn't> seem so inappropriate, does it? In particular, it shouldn't seem so> patronizing, since, as I parsed your question, it is a question a> beginner should ask. So, why decide to patronize me?Perhaps he decided to patronize you because, as *everyone* parsed yourpost, you are incapable of reading plain English but you pretend tohave the expertise to respond to questions anyway?It shouldn't seem patronizing after all, since as he (and otherrespondents) read your post, it was an answer an ignoramus mightwrite.-- You lack the ability to reason, but instead get an idea in your headand hold on to it against all evidence. I don'tfind you credible,and reject your claims, as coming from a ¤awed source. -- James S Harris shoots for === Subject: Re: Metamath Perhaps he decided to patronize you because, as *everyone* parsed your> post, you are incapable of reading plain English but you pretend to> have the expertise to respond to questions anyway?Well, I guess you must be right, then. Since *everyone* says so. Bythe way, you should note that what I said was _accurate_. I onlyresponded to the wrong question. I really don't see why my gaffe hasinspired you to post two insulting messages about me. It shouldn't seem patronizing after all, since as he (and other> respondents) read your post, it was an answer an ignoramus might> write.I'm not exactly sure why you'd want to get into a pissing contest withme. But your reply is completely pointless, since it is in responseto a post that wasn't addressed to you.'cid .95oohPS. Chill out. This has nothing to do with you. === Subject: Re: Metamath Axiom of Choice>> Also, the motivation behind proving the equivalence of the Metamath >> formulation of the Axiom of Choice and more standard formulations>> is the same as the motivation behind proving the equivalence of the >> Axiom of Choice and Zorn's Lemma, and the equivalence of the Axiom >> of Choice and the Well-Ordering Theorem. I presume that you have >> seen the proofs of these last two mentioned equivalences, Acid Pooh.> Heh. Since you appear to be goading me into replying, and I'm a> sucker for this sort of thing, here goes: I was not aware that> Metamath was a website. Nor was I aware that they had a different> version of the axiom of choice. I assumed (obviously incorrectly)> that you meant metamath to refer to Set Theory, or some such> metamathematical study. Now, in this context, my response doesn't> seem so inappropriate, does it? In particular, it shouldn't seem so> patronizing, since, as I parsed your question, it is a question a> beginner should ask. So, why decide to patronize me?I was likewise unaware that there was a Metamath site, but that factbecame abundantly clear as soon as I read D. McAnally's very rstsentence of his rst post on the subject. I suggest you go back andread it.-- Dave SeamanJudge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: Metamath Axiom of Choice>> Also, the motivation behind proving the equivalence of the Metamath >> formulation of the Axiom of Choice and more standard formulations>> is the same as the motivation behind proving the equivalence of the >> Axiom of Choice and Zorn's Lemma, and the equivalence of the Axiom >> of Choice and the Well-Ordering Theorem. I presume that you have >> seen the proofs of these last two mentioned equivalences, Acid Pooh.> > Heh. Since you appear to be goading me into replying, and I'm a> sucker for this sort of thing, here goes: I was not aware that> Metamath was a website. Nor was I aware that they had a different> version of the axiom of choice. I assumed (obviously incorrectly)> that you meant metamath to refer to Set Theory, or some such> metamathematical study. Now, in this context, my response doesn't> seem so inappropriate, does it? In particular, it shouldn't seem so> patronizing, since, as I parsed your question, it is a question a> beginner should ask. So, why decide to patronize me? I was likewise unaware that there was a Metamath site, but that fact> became abundantly clear as soon as I read D. McAnally's very rst> sentence of his rst post on the subject. I suggest you go back and> read it.It's quite obvious that I'm aware of it now. Your suggestion isappreciated, but you seem to have suffered the same mistake as me. :)'cid .95ooh === Subject: Re: Metamath Axiom of Choice> poohonlsd@yahoo.com (Acid Pooh) specically at their statement of>>the Axiom of Choice, I note that their statement of the Axiom of Choice is>> >effectively the statement that for any set x, there exists a set y such>>that for any nonempty element w of x, there is at least one element t of y>>such that w is an element of t, and that w has exactly one element in>>common with the union of all elements of y which have w as an element,>> >i.e. there is a set y such that w is an element of some element t of y,>>and if s = {t in y : w in t}, then w n (Us) has exactly one element, where>>A n B denotes the intersection of A and B, and where Us is the union of>>the elements of s.>>That this implies the Axiom of Choice is obvious (if w is a nonempty >>element of x, let f(w) be the unique element of w n (Us), where >>s = {t in y : w in t}). The question is how can one prove the Metamath>> >statement of the Axiom of Choice in ZFC?>> How does this sound for a proof. Let f : x-{empty set} -> Ux be a choice > >> function (so that f(v) is an element of v for all nonempty elements v of x). >> Let y = {{v,f(v)} : v in x, v nonempty}. The rst thing to note is that >> if w is a nonempty element of x, then there is an element of y which has w >> as an element, specically, {w,f(w)}. Let w be a nonempty element of x, >> then s = {t in y : w in t} = {{w,f(w)}} u {{v,w} : v in x, v nonempty, >> f(v) = w}, where A u B denotes the union of A and B. It follows that >> Us = {w,f(w)} u {v in x : v nonempty, f(v) = w}, and so the elements of >> Us are w, f(w), and nonempty elements v of x such that f(v) = w. Since >> w is an element of v for all nonempty elements v of x such that f(v) = w, >> then the elements of Us are w, f(w) and some sets which have w as an > >> element. By the axiom of regularity, the only common element of w and Us >> is f(w), completing the proof of the Metamath statement of the Axiom of >> Choice.>> David McAnally>> At the moment, they (the Time Lords) are far from being all-powerful.>> That's why it's been left up to me and me and me.>> quote by: Patrick Troughton in The Three Doctors>> ------->Uhm... the Axiom of Choice is an _axiom_. For specicity, it is a>wff of the FOL of set theory which is (roughly speaking) stipulated>true, and can thus be used in deductions. If you decide that you>don't like the axiom of choice, you can choose to not work with FO> >languages which include it. But even then, it's hard to deny it's use>in axiom systems which _do_ use it. (Since, by construction, you're>setting up a conditional... If the axiom of choice is true, and>...blah..., then ...blah'...)> >In any case, there is nothing to prove. As I stated above, the Metamath formulation of the Axiom of Choice is > effectively the statement that given any set x, there exists a set y > such that for all nonempty elements w of x, w n (Us) has exactly one > element, where s = {t in y : w in t}. This is not amongst the > formulations of the Axiom of Choice of which I was previously aware.> The question of the equivalence of the Metamath formulation with the> more standard versions under ZF naturally arises, as such an equivalence > is necessary if the Metamath set theoretic axioms are to be taken as > axioms of ZFC. In spite of what you might think, I was NOT trying to prove the Axiom of> Choice from ZF. If you go back initially gave a proof of a more standard version of the Axiom> of Choice from ZF *and* the Metamath version of the Axiom of Choice, and> that I was wondering about the possibility of a proof of the Metamath> version of the Axiom of Choice from ZFC (which I believe that I supplied> in the subsequent posting). In fact, I can't tell where you could have> got any idea that I was trying to prove the Axiom of Choice from ZF. Your condescendingly pointing out that the Axiom of Choice is an axiom,> and your nal statement that there is nothing to prove demonstrate that> you have completely missed the point of what I was trying to do, i.e. to> demonstrate that the axioms adopted by Metamath do in fact form a set of> axioms for ZFC, a fact which was not immediately obvious to me. Both Jesse Hughes and David Ullrich picked up what I was trying to do. Why> couldn't you?> My apologies for not reading your post more carefully.I'll have to be more careful in the future, so as not to offend thoseasking for help with my condescending remarks.'cid .95oohPS. Chill out. === Subject: Re: branch of log z> A veil has been woven out of words like imaginary and spread over> the real plane, giving the impression of an domain, accessible only> for people with special brain-power, sometimes letting the real plane> shimmering through.> introduced to me (at the college level, anyways). > The rst time i hear this, except from Caspar for me, and i'm> sincerely Yours for these words.> No. It's known to insiders, working under the veil - but it's not made> well known.That was a really long post, and you snipped the part where Imentioned that both approaches are useful. Now, quite obviously, whatI meant is that this is well known to people who are interested inmathematics. Nobody else really cares that the complex plane is justR^2. Nobody else cares that the complex eld is R^2 with some neatmultiplication thrown in. Call us insiders if you'd like... butapparently you're interested, too. So stop throwing stones, we'reboth in the glass house. Can You give me a reference, where it's said, that the i-axis and the> y-axis are just different names, but with no mathematical difference?> The same for R2, the 2D-plane, no difference to the complex plane,> argand diagramm, (gauss plane)?R^2 and the Complex plane are isomorphic if you *ignore* complexmultiplication. That is about as deep as the relationship goes. (It's quite a deep relationship, actually. But less deep than youapparently think)> Can You give me a reference, where mixed-mode-calculating is used,> like :> i*(3,4)=(-4,3) (see my calculator)?> Can You name someone, who uses the notation 3+i*4 in any> 2D-vectorspace in place of (3,4) ? The second is of course an ordered> pair of reals and the rst is using the linear-combination of two> basis-vectors (1,0) and i=(0,1) and, as the real numbers are embedded,> you ommit (1,0).> That's terrible notation. The i notation on elements from R is muchnicer. And there is no reason to use the notation a + bi when workingwith R^2, because, in particular, multiplication is not dened onR^2. So, if we want to generalize to R^n, do we need n-1 letters torepresent the n directions?> And sometimes insiders entangle in their own veil and can't see clear,> look at Algebra: What is the relation between (R2,+,r.s.m.) and> (R2,+,*)-this is called the vectorspace of complex numbers(and an> commutative eld)- and (R2,+,r.s.m.,dot)-this is the euclidian> vectorspace? branches of log ...This stuff can get messy later. -> but may be without imaginary veil a little bit less.Read Rudin's principles of mathematical analysis. Or J.E. Marsden'sComplex Analysis. Or Royden's analysis book. Or...'cid .95ooh === Subject: Re: We come from your futureTime to commit suicide... === Subject: Re: A question about Kripke semantics and physics (Was: Re: Study groups in science): So, once again, let me start with a quick Google search to: establish context.That is always a fun way to learn, and getting better every year!: If I use the search string .9526 dimensions string physics' I get about959: hits.:: For my part, I could care less about the details. It is the mathematics: through which your colleagues express their explanations that is importantto: me. The 26 dimensions are particularly interesting here because their: symmetries and invariants involved offer me an opportunity to ask you howto: think about truth and falsity in physical theory.:: Now, Galathaea has been wanting to talk about Heyting algebras and quantum: logic. Section 6.4 of the paper:: http://www.illc.uva.nl/Publications/ResearchReports/MoL-2001- 09.text.pdf:: is entitled Finite projective formulas in two variables Strangelyenough,: there are precisely 26 Heyting algebras associated with 2-universal models: discussed here. Moreover, there is not a single mention of quantumlogic.:: Now, isn't this just an amazing coincidence? Logicians tellmathematicians: about .95T' and .95F,' the physicists are talking about 26 dimensions, andmitch: knows just where to nd a paper specifying the 26 2-generated Heyting: algebras.:: Actually, I do not think it is coincidental. Unfortunately, whereas Iwould: love to offer an explanation, you would simply engage in more vulgarity.I only today got through this reference in my rst run through and stillhave much organising to get a better understanding, but I was wondering ifyou were thinking of a particular relationship here between the constraintequation in string theory and the n=2 formula in the paper. The constraintfor strings arises from a requirement for Weyl invariance of the action,which has a very interesting topological structure, so I can certainly see amotif. Have you pursued this to the next exposition stage, or are you stillhunting down the connections? This paper is very interesting!=)-- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-galathaea: prankster, fablist, magician, liar === Subject: Understanding understand the taylor exapnsion for the sinefunction,sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ...I've been told that it uses the fact that e^(i*x) = cos(x) + i*sin(x),and I can easily work out the taylor series for e^x, but I'm not surehow to use these two pieces tofind the expansion for sin(x).Any help would be === Subject: Re: trying to understand the taylor exapnsion for the sine> function, sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ... I've been told that it uses the fact that e^(i*x) = cos(x) + i*sin(x),> and I can easily work out the taylor series for e^x, but I'm not sure> how to use these two pieces to nd the Jonathan ChristensenDo you know, or know how tofind, the expansion for e^x?If so, replace the x by ix, and see what happens. === Subject: Re: Understanding taylor expansion for sine> I've been trying to understand the taylor exapnsion for the sine> function, sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ... I've been told that it uses the fact that e^(i*x) = cos(x) + i*sin(x),> and I can easily work out the taylor series for e^x, but I'm not sure> how to use these two pieces to nd the expansion for sin(x).Hello.I usually work out the Taylor series for sine around zero directly.Since you say you can easily work out the Taylor series for e^(i*x)directly, I won't go further on that point.If one plugs (i*x) into the Taylor series for e^x around zero andtakes the imaginary terms alone, doesn't one end up with the Taylorseries for sine around zero?-- Try http://csf.colorado.edu/pkt/pktauthors/Vienneau.Robert/ Bukharin.html To solve Linear Programs: .../LPSolver.htmlr c A game: .../Keynes.html v s a Whether strength of body or of mind, or wisdom, or i m p virtue, are found in proportion to the power or wealth e a e of a man is a question t perhaps to be discussed by n e . slaves in the hearing of their masters, but highly @ r c m unbecoming to reasonable and free men in search of d o the truth. -- Rousseau === Subject: Re: -0800, dzhonatan@hotmail.com (Jonathan>I've been trying to understand the taylor exapnsion for the sine>function,>>sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ...>>I've been told that it uses the fact that e^(i*x) = cos(x) + i*sin(x),>and I can easily work out the taylor series for e^x, but I'm not sure>how to use these two pieces tofind the expansion for sin(x). e^(ix) = cos(x) + i sin(x)<=> -i e^(ix) = -i cos(x) + sin(x) => sin(x) = Re(-i e^(ix))Work from there.-- I'm not interested in mathematics that might have anythingto do with reality. -- Russell Easterly, in sci.math === Subject: Re: Understanding taylor expansion for sinejust pick out the bits that has an is in.Jonathan Christensen the taylor exapnsion for the sine> function,>> sin(x) = x - x^3/3! + x^5/5! - x^7/7! + ...>> I've been told that it uses the fact that e^(i*x) = cos(x) + i*sin(x),> and I can easily work out the taylor series for e^x, but I'm not sure> how to use these two pieces tofind the expansion for sin(x).>> Any help would Understanding taylor expansion for sine > e^(i*x) = cos(x) + i*sin(x)thus sin(x) is the imaginary part of e^(ix), so you have to extract the imaginary part of the series. === Subject: UnionsLet A1 ,A2, ... be a sequence of subsets of a universal set X. Dene Ej =( Aj - {A1 U A2 U...U A(j-1)} ) where j= 1,2,3,....I was able to prove that Ei intersect = Ej empty set if i =/ j. I was alsoable to show that the union of Ek from k = 1 to n = union from k = 1 to n ofAk but I'm not sure how to prove this last statement if k goes from 1 to oo. === Subject: Re: Unions === Subject: Unions >Let A1 ,A2, ... be a sequence of subsets of a universal set X. >Dene Ej = ( Aj - {A1 U A2 U...U A(j-1)} ) where j= 1,2,3,.... >I was able to prove that Ei intersect Ej = empty set if i =/ j. >union of Ek from k = 1 to n = union from k = 1 to n of Ak >how to prove this last statement if k goes from 1 to oo. /{ Ej | j in N } = /{ Aj | j in N }/{ Ej | j in N } subset /{ Aj | j in N } is easyConversly assume x in /{ Aj | j in N } some k in N with x in Ak x in /{ Aj | j <= k } x in /{ Ej | j <= k } x in /{ Ej | j in N }---- === Subject: countable setsLet E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Provethat union of Ek as k = 1 to oo is countable. I do not need help provingthis. I need someone to explain exactly what is being asked. In Let E1, E2,E3,... be a sequence of pairwise disjoint countable sets is that sayingthat the numbers of Ei's are countable or is it saying that each Ei has acountable number of elements?? === Subject: Re: countable sets> Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove> that union of Ek as k = 1 to oo is countable. I do not need help proving> this. I need someone to explain exactly what is being asked. In Let E1, E2,> E3,... be a sequence of pairwise disjoint countable sets is that saying> that the numbers of Ei's are countable or is it saying that each Ei has a> countable number of elements?? Both. === Subject: Re: countable sets> Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove> that union of Ek as k = 1 to oo is countable. I do not need help proving> this. I need someone to explain exactly what is being asked. In Let E1, E2,> E3,... be a sequence of pairwise disjoint countable sets is that saying> that the numbers of Ei's are countable or is it saying that each Ei has a> countable number of elements??Others have explained what is being asked, but I was intrigued by yourstatement that you don't need help proving it. Now that the question hasbeen claried, you might look again at proving it.Hint: If your proof does not invoke the axiom of choice, then your proos wrong.-- Dave SeamanJudge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: countable setsDave Seaman be a sequence of pairwise disjoint countable sets.Prove> that union of Ek as k = 1 to oo is countable. I do not need help proving> this. I need someone to explain exactly what is being asked. In Let E1,E2,> E3,... be a sequence of pairwise disjoint countable sets is thatsaying> that the numbers of Ei's are countable or is it saying that each Ei hasa> countable number of elements??>> Others have explained what is being asked, but I was intrigued by your> statement that you don't need help proving it. Now that the question has> been claried, you might look again at proving it.Dave,Now that I understand the statement I will try to prove it using the axiomof choice.Onto another topic. I hope that you don't mind. I know that Mumia is notfacing a death sentence at this point but is he still physically on deathrow locked up 23 hours per day? FREE Mumia now!>> Hint: If your proof does not invoke the axiom of choice, then your proof> is wrong.>> --> Dave Seaman> Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling.> === Subject: OT (Re: countable sets)> Dave Seaman hope that you don't mind. I know that Mumia is not> facing a death sentence at this point but is he still physically on death> row locked up 23 hours per day? FREE Mumia now!Neither side was satised with Judge Yohn's decision and both sides areappealing. The possibility still exists that the death penalty could bereinstated without a new trial.-- Dave SeamanJudge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: countable sets>> Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove>> that union of Ek as k = 1 to oo is countable. I do not need help proving>> this. I need someone to explain exactly what is being asked. In Let E1, E2,>> E3,... be a sequence of pairwise disjoint countable sets is that saying>> that the numbers of Ei's are countable or is it saying that each Ei has a>> countable number of elements?? Others have explained what is being asked, but I was intrigued by your> statement that you don't need help proving it. Now that the question has> been claried, you might look again at proving it. Hint: If your proof does not invoke the axiom of choice, then your proof> is wrong.Explicitely invoked? j gWhat about N ---> N x N ---> union(E_k)where j is a suitable bijection and g(k,n) := f_k(n)is dened via given surjective maps f_k : N ---> Ek ?Marc === Subject: Re: countable sets> Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove> that union of Ek as k = 1 to oo is countable. I do not need help proving> this. I need someone to explain exactly what is being asked. In Let E1, E2,> E3,... be a sequence of pairwise disjoint countable sets is that saying> that the numbers of Ei's are countable or is it saying that each Ei has a> countable number of elements??>> Others have explained what is being asked, but I was intrigued by your>> statement that you don't need help proving it. Now that the question has>> been claried, you might look again at proving it.>> Hint: If your proof does not invoke the axiom of choice, then your proof>> is wrong.> Explicitely invoked? > j g> What about N ---> N x N ---> union(E_k)> where j is a suitable bijection and g(k,n) := f_k(n)> is dened via given surjective maps f_k : N ---> Ek ?For any given k we are given that there is a suitable surjection f_k : N-> E_k. That is, the set S_k of surjections from N onto E_k is nonemptyfor each k.How do you conclude (without AC) that there is a g: N x N -> union(E_k)?That requires choosing all the f_k's at once, and there are innitelymany of them. That is, you need to show that there is a choice functionon the set { S_k : k in N }.-- Dave SeamanJudge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: countable sets* Math Tutor> Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove> that union of Ek as k = 1 to oo is countable. I do not need help proving> this. I need someone to explain exactly what is being asked. In Let E1, E2,> E3,... be a sequence of pairwise disjoint countable sets is that saying> that the numbers of Ei's are countable or is it saying that each Ei has a> countable number of elements??... a sequence of pairwise disjount countable setscountable sets means that each Ei has a countable number ofelements.... a sequence means that the number of Eis is countable.I.e. both.-- Jon Haugsand Dept. of Informatics, Univ. of Oslo, Norway, mailto:jonhaug@i.uio.no http://www.i.uio.no/~jonhaug/, Phone: +47 22 85 24 92 === Subject: Re: countable sets: Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove: that union of Ek as k = 1 to oo is countable. I do not need help proving: this. I need someone to explain exactly what is being asked. In Let E1, E2,: E3,... be a sequence of pairwise disjoint countable sets is that saying: that the numbers of Ei's are countable or is it saying that each Ei has a: countable number of elements??Both. The E1, E2, E3, ... part says there are a countable number of E's,and pairwise disjoint *countable* sets says that each Ei is countable.Ted === Subject: Re: countable sets>Let E1, E2, E3, ... be a sequence of pairwise disjoint countable sets. Prove>that union of Ek as k = 1 to oo is countable. I do not need help proving>this. I need someone to explain exactly what is being asked. In Let E1, E2,>E3,... be a sequence of pairwise disjoint countable sets is that saying>that the numbers of Ei's are countable or is it saying that each Ei has a>countable number of elements??Both. Sequences by denition are countable ordered sets. In this casethe elements of the sequence are countable sets.-- I'm not interested in mathematics that might have anythingto do with reality. -- Russell Easterly, in sci.math === Subject: Re: Need help with proof!> Show that for arbitrary natural numbers m and n, such that 1<=m<=n the> following holds: the product n(n-1)(n-2) ...(n-m+2)(n-m+1) is dividable by> m!Here's a hint that should get you started without giving away the answer.Show that for every prime that divides m!, that prime occurs in thefactorization of n(n-1)(n-2)...(n-m+1) at least as many times as it occursin the factorization of m!.-- --Tim Smith === Subject: Re: Parity Check Matrix of a Systematic Linear Block Code> The generator matrix of a systematic linear block code has the> form G = [Ik : P]. How can it be shown that the parity check> matrix is of the form H = [-P^T : In-k]?With great ease.If a vector (a : b) is supposed orthogonal to the code generatedby G then (a : b)G^t = 0 so a + b P^t = 0 or a = -b P^t etc.Are you in the IEEE?-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlLacan, Jacques, 79, 91-92; mistakes his penis for a square root, 88-9Francis Wheen, _How Mumbo-Jumbo Conquered the World_ === Subject: Re: How fast is the Connued Fraction factorization algorithm? >>I have another question: In each of the above factorizations, only half>>(approximately) of the primes in the factor base are used. I read>>somewhere that N (the composite) must be congruent to a square modulo>>the primes in the factor base, but I don't see why:>>If x^2 = y mod N, then x^2 - y = kN, for some k. Now if a prime p (from>>the factor base) divides y, then we must have p | (x^2 - kN). So I>>conclude that kN must be congruent to a square modulo p, but that does>>not say anything about N itself? Please enlighten me. > I don't know anything about the continued fraction method> (as has been pointed out!)> but if it is like the simple quadratic sieve> one considers products of numbers of the form> Q(x) = x^2 - n> (with x close to sqrt{n})> each of which is smooth.> So one need only consider small primes p> such that n is a quadratic residue mod p. (In the multiple polynomial version one takes> Q(x) = ax^2 + 2bx + c,> with b^2 - ac = n, so that> aQ(x) = (ax + b)^2 - n> and much the same is true.)Well, using the same notation, then the continued fraction method deals with the polynomials Q(x) = x^2 - kn.-Michael. === Subject: Re: Constraints on Self-Dual Linear Block Codes> If (n,k) is a q-ary linear block code of length n and> size q^k, then in order for the code to be self-dual> it is fairly easy to show that n = 2*k. Are there any other constraints required of a code> in order for it to be self-dual?Yes ... it has to satisfy the denition of self-duality :-)-- Robin Chapman, www.maths.ex.ac.uk/~rjc/rjc.htmlLacan, Jacques, 79, 91-92; mistakes his penis for a square root, 88-9Francis Wheen, _How Mumbo-Jumbo Conquered the World_ === Subject: Re: Constraints on sha1:4g8CzI2Px2pOdQBhceYQt3njFfU=Robin Chapman a q-ary linear block code of length n and>> size q^k, then in order for the code to be self-dual>> it is fairly easy to show that n = 2*k.>> Are there any other constraints required of a code>> in order for it to be self-dual?>> Yes ... it has to satisfy the denition of self-duality :-)See the text by Roman. I know the answer to my question is yes - I was looking for clarication/insight. -- % Randy Yates % Bird, on the wing,%% Fuquay-Varina, NC % goes ¤oating by%%% 919-577-9882 % but there's a teardrop in his eye...%%%% % .95One Summer Dream', *Face The Music*, ELOhttp://home.earthlink.net/~yatescr === Subject: Re: What is a number?/What is not a number?> In said:>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that>contains Z.> So you're excluding the Cayley Numbers? Elements of nite elds?> > Yes. It was my intention to eliminate all nite elds or nite> rings for that matter. Good, that is an opinion. However, you have to exclude more. Polynomials> in one of more variables with integer coefcients for instance. They> form a ring and contain Z. Unless you would call them numbers (and> that is not common practice). I have no idea how you would exclude them.As the denition stands, they couldn't be excluded. Of course, I haveavoided dealing with the question of why we even need a label ofnumber in the rst place. If we had an answer to that question,we'd have a basis to decide how to proceed. We have three ways toproceed:1) revamp the denition above to remove polynomials,2) accept polynomials as numbers, or3) dene a number set as any mathematical set at all.In favor of 1) is a measure of psychological comfort, I suppose. Infavor of 2) is that polynomials mod ideals are isomorphic tononpolynomial rings or elds, which are already included as numbersets. In favor of 3) is that the word number is just a way to avoidsaying the wordy expression element of a mathematical set with closedbinary operation. And this brings us back to Cayley numbers.I suppose the question of what number means in common practice is atthe heart of this thread. I know of no commonly accepted denition ofnumber in mathematics, so any denition is a contender. Thatcertain mathematical objects are not usually considered as numbersis of no signicance as far as I'm concerned, because I canfind noparticular rationale to call any object a number.We could just demand that whatever objects were considered as numbersup to 1985, say, are grandfathered in as numbers, but no more forever.Or we could try to come up with a rationale for the label number andthen craft a denition on top of it.One rationale for the label number could be to regard all objectsused directly for counting or measuring as numbers. That includesthe naturals, the integers, the rationals, and the reals, but nothinglarger than that. And that leaves some sets out which are already usedas number sets, such as the complex numbers. But I'm not fond of thisrationale. However, I can't think of any rationale to dene numberwhich won't either leave some sets out or include too many.Patrick === Subject: Re: What is a number?/What is not a number?> In said:>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that>contains Z.> So you're excluding the Cayley Numbers? Elements of nite elds?> > Yes. It was my intention to eliminate all nite elds or nite> rings for that matter. Good, that is an opinion. However, you have to exclude more. Polynomials> in one of more variables with integer coefcients for instance. They> form a ring and contain Z. Unless you would call them numbers (and> that is not common practice). I have no idea how you would exclude them.As the denition stands, they couldn't be excluded. Of course, I haveavoided dealing with the question of why we even need a label ofnumber in the rst place. If we had an answer to that question,we'd have a basis to decide how to proceed. We have three ways toproceed:1) revamp the denition above to remove polynomials,2) accept polynomials as numbers, or3) dene a number set as any mathematical set at all.In favor of 1) is a measure of psychological comfort, I suppose. Infavor of 2) is that polynomials mod ideals are isomorphic tononpolynomial rings or elds, which are already included as numbersets. In favor of 3) is that the word number is just a way to avoidsaying the wordy expression element of a mathematical set with closedbinary operation. And this brings us back to Cayley numbers.I suppose the question of what number means in common practice is atthe heart of this thread. I know of no commonly accepted denition ofnumber in mathematics, so any denition is a contender. Thatcertain mathematical objects are not usually considered as numbersis of no signicance as far as I'm concerned, because I canfind noparticular rationale to call any object a number.We could just demand that whatever objects were considered as numbersup to 1985, say, are grandfathered in as numbers, but no more forever.Or we could try to come up with a rationale for the label number andthen craft a denition on top of it.One rationale for the label number could be to regard all objectsused directly for counting or measuring as numbers. That includesthe naturals, the integers, the rationals, and the reals, but nothinglarger than that. And that leaves some sets out which are already usedas number sets, such as the complex numbers. But I'm not fond of thisrationale. However, I can't think of any rationale to dene numberwhich won't either leave some sets out or include too many.Patrick === Subject: Re: What is a number?/What is not a number?> In said:>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that>contains Z.> So you're excluding the Cayley Numbers? Elements of nite elds?> > Yes. It was my intention to eliminate all nite elds or nite> rings for that matter. Good, that is an opinion. However, you have to exclude more. Polynomials> in one of more variables with integer coefcients for instance. They> form a ring and contain Z. Unless you would call them numbers (and> that is not common practice). I have no idea how you would exclude them.As the denition stands, they couldn't be excluded. Of course, I haveavoided dealing with the question of why we even need a label ofnumber in the rst place. If we had an answer to that question,we'd have a basis to decide how to proceed. We have three ways toproceed:1) revamp the denition above to remove polynomials,2) accept polynomials as numbers, or3) dene a number set as any mathematical set at all.In favor of 1) is a measure of psychological comfort, I suppose. Infavor of 2) is that polynomials mod ideals are isomorphic tononpolynomial rings or elds, which are already included as numbersets. In favor of 3) is that the word number is just a way to avoidsaying the wordy expression element of a mathematical set with closedbinary operation. And this brings us back to Cayley numbers.I suppose the question of what number means in common practice is atthe heart of this thread. I know of no commonly accepted denition ofnumber in mathematics, so any denition is a contender. Thatcertain mathematical objects are not usually considered as numbersis of no signicance as far as I'm concerned, because I canfind noparticular rationale to call any object a number.We could just demand that whatever objects were considered as numbersup to 1985, say, are grandfathered in as numbers, but no more forever.Or we could try to come up with a rationale for the label number andthen craft a denition on top of it.One rationale for the label number could be to regard all objectsused directly for counting or measuring as numbers. That includesthe naturals, the integers, the rationals, and the reals, but nothinglarger than that. And that leaves some sets out which are already usedas number sets, such as the complex numbers. But I'm not fond of thisrationale. However, I can't think of any rationale to dene numberwhich won't either leave some sets out or include too many.Patrick === Subject: Re: What is a number?/What is not a number?>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that>contains Z.>So ordinal numbers are not numbers?-- Stephen J. Herschkorn herschko@rutcor.rutgers.edu === Subject: Re: What is a number?/What is not a number?>>>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that> >contains Z.> So ordinal numbers are not numbers?Good point. OK, a number is an element of a number set. A number setis eithera) the set of integers Z orb) any ring/eld/algebra R that contains Z orc) any of the ordinal or cardinal objects dened by Cantor.I think it's beginning to look like a weaker denition is in orderfor number set. Let's look at some possibilities. A number set is1) any set that has a closed binary operation dened on all pairs of elements of the set,2) any semigroup, or3) any totally orderable set.But these possible denitions may be too weak. The advantage of 1) isthat it allows people to call the elements of their favorite setnumbers if they choose to do so. It seems to me that pure whim isthe driving force behind what set elements have been generallyaccepted to be called numbers.Maybe the desire to label set elements as numbers lies in thepsychological need of people to reify their favorite sets. And if thishypothesis of ontology being at the root of the number issue istrue, then the term imaginary number is an oxymoron, or at the veryleast an equivocation. Perhaps the orgin of the number concept isPlatonistic at heart. In any case, it seems too late to return to thetime when number was associated with counting or measuring. Then whatis a number?Patrick === Subject: Re: What is a number?/What is not a number?>>I'll offer this denition: A number is an element of a number set. A>>number set is either the set of integers Z or any ring/eld R that>>contains Z.> So ordinal numbers are not numbers?It seems even the natural numbers are not numbers.-- Dave SeamanJudge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: What is a number?/What is not a number?>>I'll offer this denition: A number is an element of a number set. A>>number set is either the set of integers Z or any ring/eld R that>>contains Z.> So ordinal numbers are not numbers? It seems even the natural numbers are not numbers.I addressed that issue on my post of the fourteenth.Patrick === Subject: Re: What is a number?/What is not a number?@mozo.cc.purdue.edu:>I'll offer this denition: A number is an element of a number set. A>number set is either the set of integers Z or any ring/eld R that>contains Z.>> So ordinal numbers are not numbers? It seems even the natural numbers are not numbers. > So Numbers are not numbers;)-- If its Monday then I am a fool but not ignorant.Its Wenesday === Subject: Re: What is a number?/What is not a number?> @mozo.cc.purdue.edu: >>>I'll offer this denition: A number is an element of a number set. A> >number set is either the set of integers Z or any ring/eld R that>contains Z.>>> So ordinal numbers are not numbers?> It seems even the natural numbers are not numbers.> So Numbers are not numbers> ;)The question is, What is it we really mean by the label number?There are two ways to dene the set of number sets: One way is tosimply list all number sets, the other is to give a rule (given by adenition) that takes the place of the listing of number sets. Myquestion is, Is there a denition that provides a rule that createsthe same set of number sets as there are in the set of number setscreated as a listing by at?So, we have the set of number sets S = {N, Z, Rationals, Reals,Complex, Cayley, ...}. So, what denition of number gives us theset S?Look at it this way: Let S' = {M : P(M), where M is a mathematicalset}. What denition do we propose such that 1) M is a number set iffP(M) is true, and 2) such that S' = S?Is there a mathematical or set-theoretic property P(M) common to allthose number sets M listed in S (other than convention says thatthey should be listed there)?Patrick === Subject: Matrix convert from 1 coordinate space to another where they-axis is inverted.In the 1st space, the 3x3 transformation matrix is specied as with +ve yupwards:a b 0c d 0e f 1in the 2nd space :a c eb d f0 0 1where in the 2nd space y is downwards.I've worked out by trial and error that by negating b & c the conversion issuccessful so thata -c e-b d f0 0 1will make everything work for my conversion.what I understand is to do a ¤ip of y-axis one needs to multiply the matrixby :1 0 00 -1 00 0 1but that doesn't givea -c e-b d f0 0 1Is there somehting more to a transpose than simply ¤ipping along === Subject: Re: A trend ?> Hi Dan Weiner,> Re: How I feel about your one word posts,> You added two words: duly noted ,> Do I detect a trend here ? But will his next post have three words or four?Reminds me of a story told about President Calvin Coolidge, known asSilent Cal.A woman reporter once approached him and said, My editor bet me thatI couldn't get more than two words out of you.The President replied, You Lose.Double-A === Subject: x^2 + y^4 = z^4+ y^4 = z^4 has no positive-integer solutions. Is the proof of this result short enough for some kind soul to post it, or need I make a trip to the library? (I have citations.)-- Stephen J. Herschkorn herschko@rutcor.rutgers.edu === Subject: Re: x^2 + y^4 = z^4 === Subject: x^2 + y^4 = z^4 >x^2 + y^4 = z^4 has no positive-integer solutions. Is the proof of >this result short enough for some kind soul to post it, or need I >make a trip to the library? (I have citations.)When youfind proof, let us know.It's one that's been pestering me for ages.Here's my archived thoughts upon x^2 + y^4 = z^4 for pairwise coprime x,y,zIf y odd: y^4 = z^4 - x^2 = (z^2 - x)(z^2 + x); factors odd, coprime y^4 = u^4 v^4; x = (u^4 - v^4)/2; z^2 = (u^4 + v^4)/2If x odd: x^2 = z^4 - y^4 = (z - y)(z + y)(z^2 + y^2); factors odd, coprime x^2 = u^2 v^2 w^2; y = (u^2 - v^2)/2; z = (u^2 + v^2)/2 w^2 = z^2 + y^2 = (u^4 + v^4)/2Thus problem boils down to showing no coprime a,b,c with a^4 + b^4 = 2c^2when a /= b.Is there some coprime a,b,c with a^2 + b^2 = 2c^2and a /= b?-- this is innite descent proof, not quickno solution in positive integers to the equation x^4 + y^4 = z^2http://www.math.toronto.edu/mathnet/plain/questionCorner/ fermat4.html---- === Subject: Re: x^2 + y^4 = z^4> Subject: x^2 + y^4 = z^4> Thus problem boils down to showing no coprime a,b,c with> a^4 + b^4 = 2c^2> when a /= b. Is there some coprime a,b,c with> a^2 + b^2 = 2c^2> and a /= b?Yes, 1^2 + 7^2 = 2*5^2 7^2 + 23^2 = 2*17^2 , etca^2 + b^2 = 2c^2suggests you are looking at the normof (1+i)(p +iq)^2 in Z(i)This givesa = p^2 - q^2 - 2pqb = p^2 - q^2 + 2pq(a,b) = 1, (p,q)=1 => p,q not both oddSome kind of descent might be possible in === Zor even more likely in Z(i)Subject: Re: x^2 + y^4 = z^4 === Subject: x^2 + y^4 = z^4>> Thus problem boils down to showing no coprime a,b,c with> a^4 + b^4 = 2c^2> when a /= b.>> Is there some coprime a,b,c with> a^2 + b^2 = 2c^2> and a /= b?>******************************************************** Well, (2m^2-1)^2 + (2m^2-4m+1)^2 = 2(2m^2-2m+1)^2._______________________________________________ __________Eric J. Wingler (wingler@math.ysu.edu)Dept. of Mathematics and StatisticsYoungstown State UniversityOne University PlazaYoungstown, OH 44555-0001330-941-1817 === Subject: Re: x^2 + y^4 = z^4>Is there some coprime a,b,c with> a^2 + b^2 = 2c^2>and a /= b?There are innitely many positive integer solutions to, for example,1^2 + b^2 = 2*c^2 (see Pell's equation).Robert Israel israel@math.ubc.caDepartment of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: tensors for totsHow far can one get in understanding the structure of tensors at apoint on a manifold in terms of our old school friends column vectors,row vectors and matrices? Even in general relativity all we have ateach point on the manifold is a real vector space with fourcomponents, so it seems we can go all the way -- but I'm havingtrouble with some of the mappings.Shall I show what work you've done so far, or would somebody care totake the ball from there... ? === Subject: Re: tensors for tots> How far can one get in understanding the structure of tensors at a> point on a manifold in terms of our old school friends column vectors,> row vectors and matrices? Even in general relativity all we have at> each point on the manifold is a real vector space with four> components, so it seems we can go all the way -- but I'm having> trouble with some of the mappings. Shall I show what work you've done so far, or would somebody care to> take the ball from there... ? You can get very far. Since you can't even understand the word structure, never tensors, or even such nonsense as curved space-time without vectors. First you build a 3 dimensional school. Then you build an 4-dimensional box. Then you build an n-dimensional table. Then you rotate the table n+1 times, so that 1 is now at the origin. Then you build a radioactive GPS robot orbiting the Earth. Then you tell mathematicians to go back to school, and teach chemists something about logic, since not only doesn't cold-fusion work at negative temperatures, it doesn't even work at imaginary temperatures. === Subject: Re: tensors for tots> How far can one get in understanding the structure of tensors at a> point on a manifold in terms of our old school friends column vectors,> row vectors and matrices?Very far, I think. Start with a vector space. A vector is clearlyindependent of his coordinates referring to a special basis, so howdo the coordinates change, when we change the basis? The answer ofLinear Algebra is: Let B be the matrix of the change of the basis,and v be the (column-)vector of coordinates with respect to the old basis. Then the new coordinates w are given byw = B^(-1) v.B^(-1)'s name in SRT is often Lambda mu nu.A vector is a contravariant vector, so to say, an (1,0)-Tensor.Now consider a linear mapping from the vector space to the eld ofscalars, represented by a row v*. How do the coordinates change? LAsays, the new coordinates w* arew* = v* B^T(Multiplication from the right with the Transposed of B)B^T's name in SRT is often Lambda tilde (swung dash) mu nu.A co-vector is a covariant vector, an (0,1)-Tensor.A Matrix consists of rows and colums, so it is a (1,1)-Tensor.Generally speaking, a (m,n)-Tensor is a tuple of m contravariantvectors (= vectors, tangent vectors) and n covariant vectors(= co-vectors, cotangent vectors).OK?Best wishes, Alm === Subject: Re: tensors for tots> How far can one get in understanding the structure of tensors at a> point on a manifold in terms of our old school friends column vectors,> row vectors and matrices? Very far, I think. Start with a vector space. A vector is clearly> independent of his coordinates referring to a special basis, so how> do the coordinates change, when we change the basis? The answer of> Linear Algebra is: Let B be the matrix of the change of the basis,> and v be the (column-)vector of coordinates with respect to the old > basis. Then the new coordinates w are given by> w = B^(-1) v.> B^(-1)'s name in SRT is often Lambda mu nu.> A vector is a contravariant vector, so to say, an (1,0)-Tensor.> Now consider a linear mapping from the vector space to the eld of> scalars, represented by a row v*. How do the coordinates change? LA> says, the new coordinates w* are> w* = v* B^T> (Multiplication from the right with the Transposed of B)> B^T's name in SRT is often Lambda tilde (swung dash) mu nu.> A co-vector is a covariant vector, an (0,1)-Tensor.> A Matrix consists of rows and colums, so it is a (1,1)-Tensor.> Generally speaking, a (m,n)-Tensor is a tuple of m contravariant> vectors (= vectors, tangent vectors) and n covariant vectors> (= co-vectors, cotangent vectors).> OK?Darn ... I've been given a certain number of credits here, butsquandered a number of them by loosely parsing the question -- like agenie who grants three wishes, and debits one when you say I wish Ihad more time to think.I'm familiar with the idea of change of basis and of matrices actingon vectors to express the vectors in terms of new bases, but I'm notentirely sure why you call the inverse of (the thing which multipliescolumn vectors to get new forms of column vectors) the matrix of thechange of basis. I would just call the thing itself by this title: v' = Bv (column vectors, square matrix). But let that pass.I am also familiar with the idea of transforming matrices themselvesto a new basis. If B is the transformation matrix (in my sense),then the prescription for transforming a matrix A is: A' = BAB^(-1)which can be read to say that, given a vector expressed in the newbasis, we rst transform it back to the old basis, operate with theold matrix, then transform again to the new basis. (You apparentlywould reverse the symbols B and B^(-1)). I'm sure you can followso far what I'm exrpessing on my simple minded level, even if youmight prefer to express it slightly differently.Now here is where I run into difculty: if we say that v' = Bv (mynotation), then I'm uncertain how we wish to transform v*(v-transpose, a row vector). Or for that matter, say we want v* tobe the dual vector corresponding to v: I'm uncertain when we wouldsimply want to set v* = v^t, and when we want to do something morecomplicated.I have a hunch this has to do with the metric tensor ... oh yeah, wehaven't introduced that yet. I also have a hunch this has to do withwhether we content ourselves with orthogonal transformations ofcoordinates, so that B^1 = B^t, or go for the gusto with general(invertable) linear transformations.This is the level I would like to be able to understand with dinkymatrices before trying to understand the differential manifold case,since as you seem to agree the somethingomorphism is complete at eachpoint. I also hope not to get hung up on any terminological problemsbetween math and physics, perhaps by saying things like we'd likethis object to be invariant, instead of using terms like covariantand contravariant, to start.Anyway, to take one more baby step, if I have not exhausted mycredits, am I correct in thinking that a reasonable way to introduce ametric tensor into babyland would be to dene the inner product ofa row vector and a column vector, in a particular coordinate system,to be a bilinear form with a matrix sandwiched in the middle, thatmatrix our metric? === Subject: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin thesis)Stephen Dave Seaman:> A set is recursive if there is an effective procedure (a Turing machine,> perhaps) that can decide membership in the set. That is, the machine> halts and returns 1 if the input is in the set, and the TM halts and> returns 0 if the input is not in the set.This is the denition of a decidable language at wikipedia:http://en.wikipedia.org/wiki/Decidable_languageA decidable or recursive language is a formal language that is a recursiveset, i.e., for which there exists an algorithm to solve the followingdecision problem: Given string w, does w belong to the language? Thealgorithm is not allowed to run into an innite loop and has to produce aYES/NO answer for any input string after a nite amount of time. Toformalize the rather vague term algorithm, one usually employs Turingmachines, but several other equivalent approaches are possible.This denition should say nite number of steps instead of niteamount of timeI will come back to this.This is the denition of a recursively enumerable language:http://en.wikipedia.org/wiki/Recursively_enumerable_ languageDenition 1. Given string w as input, the algorithm halts and outputs YESif and only if w belongs to the language L. If w does not belong to thelanguage L, the algorithm either runs forever, or halts and outputs NO.There is a second denition that you might want to read.Let me dene a language, L, that consists of all unary representations ofnatural numbers.1 = one, 11 = two, 111 = three, etc.This language is recursively enumerable. Given a string, x, there exists aTM thatwill halt after a nite number of steps if x is a member of L.This language is NOT decidable. Consider what happens if x is an innitestringof 1's. The TM will not halt after a nite number of steps.The set of all natural numbers is not a recursive set.Consider what happens when we talk about the set of all TM's.Assume we can encode the state transition table of a TM usinga natural number. This set can not be recursive for the samereason that the natural numbers are not recursive. Given astring, i, we can not be sure that TM(i) is actually a TMbecause we can not be sure that i is actually a natural number.No set can contain every computable natural number.Proof:Assume a TM produces a tape with all of the natural numbersencoded in unary where each natural is followed by a 0 (or a blank).Turing gives the state transition table of such a TM 010110111011110...I can dene a three state TM that willfind a natural numberthat is not on this tape:1) Read right until there is a 0.2) Read right until a second 0 is found.3) Backup and write a 1 on the previous 0.Repeat steps (1) through (3).This TM will always produce a tape that has exactly one 0.This 0 will be at a nite position on the tape and the string of 1'sthat preceds this 0 represents a natural number that was not onthe original input tape.The Halting Problem is ill posed.There is no set that contains every TM just as there is no setthat contains every computable natural number.Now, about the difference between nite amount of time vsnite number of steps. There are theories of computing wherea TM can perform an innite number of steps in nite time.These are called hypercomputers.http://en.wikipedia.org/wiki/HypercomputerA non-deterministic Turing machine is an example of a hypercomputer.Another example is an accelerated Turing Machine. An ATM performsthe rst operation in one unit of time, the second operation is 1/2 unitof time, the third operation in 1/4 unit of time, etc. An ATM will performan innite number of operations after two units of time.Assume we have a computer that can perform an operation in onenanosecond. The language, L, that I dened above is not evenrecognizable if we expect an answer before the universe freezes over.We can easily compute a natural number, n, that is so large thatour nanosecond computer will take 15 billion years to recognizen as a natural number. There is only a nite number of naturalsless than or equal to n. There is an innite number of naturalslarger than n. Nearly all natural numbers are larger than n.So, we see that we have to assume that a TM can performan innite number of operations in nite time to even saythat L is recursively enumerable.Russell- Zeno was right. Motion is impossible. === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin of all natural numbersis the function (lambda x )[1]. (I am using Church's excellent lambdanotation for functions.) All constant functions are recursive. Fora trivial proof see: _Computability and Unsolvability_ by Martin Davisor _Theory of Recursive Functions and Effective Computability_ by Rogers.In fact, in the latter source, see page 6 where the author denes theclass of primitive recursive functions. This is quite a standard denition(although equivalent alternatives exist in the literature). You willsee that (lambda x)[1] is primitive recursive by denition. It is well-knownthat the primitive recursive functions are recursive (and indeed thisis often part of the denition of recursive function). Therefore, theset of natural numbers is not only recursive, it is primitive recursive.This is all quite trivial and should be mastered on the rst day of studyingrecursion theory.-Leonard Blackburn === Subject: Re: No Set Contains Every Computable function of the set of all natural numbers> is the function (lambda x )[1]. (I am using Church's excellent lambda> notation for functions.) All constant functions are recursive. For> a trivial proof see: _Computability and Unsolvability_ by Martin Davis> or _Theory of Recursive Functions and Effective Computability_ by Rogers.> In fact, in the latter source, see page 6 where the author denes the> class of primitive recursive functions. This is quite a standarddenition> (although equivalent alternatives exist in the literature). You will> see that (lambda x)[1] is primitive recursive by denition. It iswell-known> that the primitive recursive functions are recursive (and indeed this> is often part of the denition of recursive function). Therefore, the> set of natural numbers is not only recursive, it is primitive recursive.> This is all quite trivial and should be mastered on the rst day ofstudying> recursion theory.>I haven't read Computability and Unsolvability orTheory of Recursive Functions and Effective ComputabilityI didfind a reference to Theory of Recursive Functions and EffectiveComputability at Mathworld:http://mathworld.wolfram.com/ GeneralRecursiveFunction.htmlThere are two camps of thought on the meaning of general recursive function.One camp considers general recursive functions to be equivalent to the usualrecursive functions. For members of this camp, the word general emphasizesthat the class of functions includes all of the specic subclasses, such asthe primitive recursive functions (Rogers 1987, p. 27).The other camp considers general recursive functions to be equivalent tototal recursive functions.This is Mathwrld's denition of total recursive functions:http://mathworld.wolfram.com/RecursiveFunction.htmlA recursive function is a function generated by (1) addition, (2)multiplication, (3) selection of an element from a list, and (4)determination of the truth or falsity of the inequality a < b according tothe technical rules:1. If F and the sequence of functions G1,G2,G3, ..., Gn are recursive, thenso is F(G1,G2,...Gn).2. If F is a recursive function such that there is an x for each a with ,then the smallest x can be obtained recursively.A Turing machine is capable of computing recursive functions.My approach assumes computable means TM computable.My argument falls into the other camp.I am using the denition of decidable language given at wikipedia:A decidable or recursive language is a formal language that is a recursiveset, i.e., for which there exists an algorithm to solve the followingdecision problem: Given string w, does w belong to the language? Thealgorithm is not allowed to run into an innite loop and has to produce aYES/NO answer for any input string after a nite amount of time. Toformalize the rather vague term algorithm, one usually employs Turingmachines, but several other equivalent approaches are possible.All regular, context-free and context-sensitive languages are recursive, butthere exist recursively enumerable languages that are not recursive; oneexample is given by the halting problem.I have shown why a Turing machine can not decide if a string, w, representsa natural number.wikipedia says several other equivalent approaches are possible.Roger's denition can not be one of these equivalent approaches.The set of all natural numbers is not a recursive set if our denitionof recursive set requires there exist a TM that can decide membershipin the set. Mathworld's denition indicates there are differencesbetween denitions of general recursive function.This appears to be one of those differences.Russell- 2 many 2 count === Subject: Re: No Set Contains Every Computable Natural > I am using the denition of decidable language given at wikipedia: A decidable or recursive language is a formal language that is a recursive> set, i.e., for which there exists an algorithm to solve the following> decision problem: Given string w, does w belong to the language? The> algorithm is not allowed to run into an innite loop and has to produce a> YES/NO answer for any input string after a nite amount of time. To> formalize the rather vague term algorithm, one usually employs Turing> machines, but several other equivalent approaches are possible. Note that it says a nite amount of time.> All regular, context-free and context-sensitive languages are recursive,> but there exist recursively enumerable languages that are not recursive;> one example is given by the halting problem. Did you realize that the natural numbers in unary (or binary, or any standard base) is a *regular* language, and hence context-free, and recursive (i.e. decidable.). You reference this site, and then you try to make claims contradicting them.> I have shown why a Turing machine can not decide if a string, w,> represents a natural number. That's because you think the string of an innite number of 1s is a natural number. Once again, you have to understand that every natural number is nite, even in unary representation.> The set of all natural numbers is not a recursive set if our denition> of recursive set requires there exist a TM that can decide membership> in the set. Mathworld's denition indicates there are differences> between denitions of general recursive function.> This appears to be one of those differences. Did you even notice that your denitions of these sets are based on *formal languages* ? Did you even look up what a formal language is? Here you go, from Wikipedia:> In mathematics, logic and computer science, a formal language is a> set of nite-length words (or strings) over some nite alphabet. Note that a formal language is a set of FINITE-LENGTHED strings.J === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin message>> Stephen Harris if there is an effective procedure (a Turing machine,> perhaps) that can decide membership in the set. That is, the machine> halts and returns 1 if the input is in the set, and the TM halts and> returns 0 if the input is not in the set.> This is the denition of a decidable language at wikipedia:> http://en.wikipedia.org/wiki/Decidable_language>> A decidable or recursive language is a formal language that is a recursive> set, i.e., for which there exists an algorithm to solve the following> decision problem: Given string w, does w belong to the language? The> algorithm is not allowed to run into an innite loop and has to produce a> YES/NO answer for any input string after a nite amount of time. To> formalize the rather vague term algorithm, one usually employs Turing> machines, but several other equivalent approaches are possible.>> This denition should say nite number of steps instead of nite> amount of time> I will come back to this.>A TM is an abstract logical computing machine (Turing: LCM)which does not consume physical resources. Those Super-Turingmachines you mention later have an abstract property that TMsdo not. They represent the real numbers (...Pi) with innite precision.This is not physically realizable.> This is the denition of a recursively enumerable language:> http://en.wikipedia.org/wiki/Recursively_enumerable_language>> Denition 1. Given string w as input, the algorithm halts and outputs YES> if and only if w belongs to the language L. If w does not belong to the> language L, the algorithm either runs forever, or halts and outputs NO.>> There is a second denition that you might want to read.>> Let me dene a language, L, that consists of all unary representations of> natural numbers.> 1 = one, 11 = two, 111 = three, etc.>> This language is recursively enumerable. Given a string, x, there exists a> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is an innite> string> of 1's. The TM will not halt after a nite number of steps.>> The set of all natural numbers is not a recursive set.>http://www.cs.auckland.ac.nz/CDMTCS/chaitin/ omega.htmlAnyway, it was Post who put his nger on the essential idea, which is thenotion of a set of objects that can be generated one by one by a machine, insome order, any order. In other words, there is an algorithm, a computerprogram, for doing this. And that's the essential content of the notion of aFAS, that's the toy model that I'll use to study the limits of the formalaxiomatic method. I don't care about the details, all that matters to me isthat there's an algorithm for generating all the theorems, that's the keything.And since this is such an important notion, it would be nice to give it aname! It used to be called an r.e. or recursively enumerable set. Theexperts seem to have switched to calling it a computably enumerable orc.e. set. I'm tempted to call it something that Post said in one of hispapers, which is that it's a generated set, one that can be generated byan algorithm, item by item, one by one, in some order or other, slowly butsurely. But I'll resist the temptation!FAS = c.e. set of mathematical assertionsSo what's the bottom line? Well, it's this: Hilbert's goal of one FAS forall of math was an impossible goal, because you can't put all ofmathematical truth into just one FAS. Math can't be static, it's got to bedynamic, it's got to evolve. You've got to keep extending your FAS, addingnew principles, new ideas, new axioms, just as if you were a physicist,without proving them, because they work! Well, not exactly the way thingsare done in physics, but more in that spirit. And this means that the ideaof absolute certainty in mathematics becomes untenable. Math and physics maybe different, but they're not that different, not as different as peoplemight think. Neither of them gives you absolute certainty!SH: I brought this up because of:...According to Turing's denition, a number is computable its decimal expansion can be written down by a circle freemachine. This is a machine that performs an nitely many,Turing denes the machine to be circular. Circular machinesreach a conguration from which there is no possible move,or go on moving, but do not print any more symbols.SH: There is a signicant difference between a circle-freemachine that works at printing out the innitely long digitsof Pi and a circular machine that may move but not printany more output --> no symbols so it is no longer generating.A generated set, one that can be generated by an algorithm,item by item, one by one, in some order or other, slowly but surely.Computing Pi is not an example of the .95halting problem' justbecause it does not halt. The circular machine is an exampleof the halting problem. I keep getting the impression that youthink these are analgous situations just because they dont halt.COMPUTABILITY AND RECURSION 285 Robert SoareDenition 1.2. (i) A function is Turing computable if it is denable bya Turing machine, as dened by Turing 1936. (See [Kleene, 1952] or[Soare, 1987].)(ii) A set A is computably enumerable (c.e.) if A is (/) or is the rangeof a Turing computable function.(iii) A function f is recursive if it is general recursive, as dened byG ~odel 1934. (See also Kleene's variant 1936, 1943, and [1952, p. 274].)(iv) A set A is recursively enumerable (r.e.) if A is (/) or is the range ofageneral recursive function.Recursively Enumerable Reals and Chaitin Omega NumbersCristian S. Calude, Peter H. Hertling, Bakhadyr Khoussainov, Y. WangA real number alpha is called recursively enumerable if it is the limit ofarecursive, increasing, converging sequence of rationals.Roughly speaking, the computational depth of an object is the amount of timerequired for an algorithm to derive the object from its shortestdescription. Bennett showed that the characteristic sequence XK of thehalting problem is strongly deep, while no random sequence is strongly deep.Investigating this matter further, Juedes, Lathrop, and Lutz have consideredthe notion of usefulness'' of innite sequences. A sequencex is useful if all recursive sequences can be computed with oracle accessto x within a xed recursive time bound. For example XK is useful, whileno recursive or random sequence is useful.> Consider what happens when we talk about the set of all TM's.> Assume we can encode the state transition table of a TM using> a natural number. This set can not be recursive for the sameWikipedia:A set S of natural numbers or tuples of natural numbers, or of literalstrings, is recursively enumerable or computably enumerable orsemi-decidable if it satises either (and therefore both) of the followingequivalent conditions. a.. There is an algorithm that, when given a natural number n (or tuple ofnatural numbers, or word, as the case may be) eventually halts if n is amember of S and otherwise runs forever. a.. There is an algorithm that generates the members of S. That meansthat its output is simply a list of the members of S: s1, s2, s3, ... Ifnecessary it runs forever.Natural numbers have two main purposes: they can be used for counting(there are 3 apples on the table), or they can be used for ordering(this is the 3rd largest city in the state).> reason that the natural numbers are not recursive. Given a> string, i, we can not be sure that TM(i) is actually a TM> because we can not be sure that i is actually a natural number.>Some problems are recursively enumerable but not recursive. Oneexample is the halting problem, which is the problem: Given a program and input parameters, will that program eventually halt when run with those parameters?> No set can contain every computable natural number.>> Proof:> Assume a TM produces a tape with all of the natural numbers> encoded in unary where each natural is followed by a 0 (or a blank).> Turing gives the state transition table of such a TM> 010110111011110...>> I can dene a three state TM that will nd a natural number> that is not on this tape:>> 1) Read right until there is a 0.> 2) Read right until a second 0 is found.> 3) Backup and write a 1 on the previous 0.> Repeat steps (1) through (3).>> This TM will always produce a tape that has exactly one 0.> This 0 will be at a nite position on the tape and the string of 1's> that preceds this 0 represents a natural number that was not on> the original input tape.>SH: The successor function builds the whole set of natural numbersWikpedia:a.. There is a natural number 0.a.. Every natural number a has a successor, denoted by a + 1.a.. There is no natural number whose successor is 0.Distinct natural numbers have distinct successors: if a ? b, then a + 1 ? b+1If a property is possessed by 0 and also by the successor of every naturalnumber which possesses it, then it is possessed by all natural numbers.(This postulate ensures that the proof technique of mathematical inductionis valid.)> The Halting Problem is ill posed.> There is no set that contains every TM just as there is no set> that contains every computable natural number.>The set of natural numbers in countably innite and has no greatestor last digit. The set can be represented as {0,1,2,3,...}which doesnot list the entire set or assume it has a largest digit.just as there is no set that contains every computable natural numberIf you want to establish a set that has one-to-one correspondencebetween TMs which terminate after 1 step, 2 steps, 3 steps and so on,and the natural numbers, it seems reasonable to me. What systematicmethod do you have that eliminates the computable natural numbersand excludes them from the set of real numbers? I suspect you meanthe computable numbers cannot be sorted out of the reals. I amnot sure there is an algorithm to list computable transcendentals.I am not much interested in those === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin thesis)Russell Easterly Dave Seaman:> A set is recursive if there is an effective procedure (a Turing machine,> perhaps) that can decide membership in the set. That is, the machine> halts and returns 1 if the input is in the set, and the TM halts and> returns 0 if the input is not in the set.> This is the denition of a decidable language at wikipedia:> http://en.wikipedia.org/wiki/Decidable_language>> A decidable or recursive language is a formal language that is a recursive> set, i.e., for which there exists an algorithm to solve the following> decision problem: Given string w, does w belong to the language? The> algorithm is not allowed to run into an innite loop and has to produce a> YES/NO answer for any input string after a nite amount of time. To> formalize the rather vague term algorithm, one usually employs Turing> machines, but several other equivalent approaches are possible.>> This denition should say nite number of steps instead of nite> amount of time> I will come back to this.>> This is the denition of a recursively enumerable language:> http://en.wikipedia.org/wiki/Recursively_enumerable_language>> Denition 1. Given string w as input, the algorithm halts and outputs YES> if and only if w belongs to the language L. If w does not belong to the> language L, the algorithm either runs forever, or halts and outputs NO.>> There is a second denition that you might want to read.>> Let me dene a language, L, that consists of all unary representations of> natural numbers.> 1 = one, 11 = two, 111 = three, etc.>> This language is recursively enumerable. Given a string, x, there exists a> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is an innite> string> of 1's. The TM will not halt after a nite number of steps.>You can't input an innite string to the tape. If you could, it wouldn'tbe a Turing machine.> The set of all natural numbers is not a recursive set.>No natural number requires an innite unary representation. All may berepresented using a nite number of 1s.> Consider what happens when we talk about the set of all TM's.> Assume we can encode the state transition table of a TM using> a natural number. This set can not be recursive for the same> reason that the natural numbers are not recursive. Given a> string, i, we can not be sure that TM(i) is actually a TM> because we can not be sure that i is actually a natural number.>All Turing machines can be nitely represented. There is no such thing asa TM transition function that requires an innite state automata forrepresentation.> No set can contain every computable natural number.>> Proof:> Assume a TM produces a tape with all of the natural numbers> encoded in unary where each natural is followed by a 0 (or a blank).This is impossible, a) a decider is limited to a nite number of stepsbefore halting, b) to output all integers in unary requires an inifnitenumber of steps - hence, no TM can produce this output.> Turing gives the state transition table of such a TM> 010110111011110...>> I can dene a three state TM that will nd a natural number> that is not on this tape:>> 1) Read right until there is a 0.> 2) Read right until a second 0 is found.> 3) Backup and write a 1 on the previous 0.> Repeat steps (1) through (3).>> This TM will always produce a tape that has exactly one 0.> This 0 will be at a nite position on the tape and the string of 1's> that preceds this 0 represents a natural number that was not on> the original input tape.>You have not at all proven this. First, how can there be a 0 at a niteposition from the start? If there is, there must a 0 to its right (in factan innite number of zeros), hence step 2 will read this second zero, andstep 3 will go back and erase the .95remaining 0'. The part about the numberpreceding the last 0 being an integer not on the tape makes no sense either.> The Halting Problem is ill posed.> There is no set that contains every TMSure there is : A = { | M is a valid TM representation}It is easy to check, given a data structure, whether the input is a valid TMor not.> just as there is no set> that contains every computable natural number.>All natural numbers are computable. However, they _all_ can't be generatedin a single run of any algorithm/TM.> Now, about the difference between nite amount of time vs> nite number of steps. There are theories of computing where> a TM can perform an innite number of steps in nite time.> These are called hypercomputers.> http://en.wikipedia.org/wiki/Hypercomputer>> A non-deterministic Turing machine is an example of a hypercomputer.No, an NTM is not a hyper-computer since any NTM can be simulated by astandard TM. The NTM must be given additional abilities to becomesuper-Turing.> Another example is an accelerated Turing Machine. An ATM performs> the rst operation in one unit of time, the second operation is 1/2 unit> of time, the third operation in 1/4 unit of time, etc. An ATM will perform> an innite number of operations after two units of time.>> Assume we have a computer that can perform an operation in one> nanosecond. The language, L, that I dened above is not even> recognizable if we expect an answer before the universe freezes over.> We can easily compute a natural number, n, that is so large that> our nanosecond computer will take 15 billion years to recognize> n as a natural number. There is only a nite number of naturals> less than or equal to n. There is an innite number of naturals> larger than n. Nearly all natural numbers are larger than n.>> So, we see that we have to assume that a TM can perform> an innite number of operations in nite time to even say> that L is recursively enumerable.>To say that there is some natural number that a physical computer will neverbe able to print out in unary is one thing, but to say that a TM (a purelymathematical object) .95can't' print out certain natural numbers in unary in anite number of steps is not correct.l8r, Mike N. Christoff === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin thesis)Michael N. Christoff This is the denition of a recursively enumerable language:>> > This language is recursively enumerable. Given a string, x, there existsa> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is an>> innite string of 1's. The TM will not halt after a nite number ofsteps.> > You can't input an innite string to the tape. If you could, it wouldn't> be a Turing machine.>No, but you can input nite instructions which generate innite output.Russell is right about Turing saying this, and I found it repeated:A Highly Random Number by Becher, Daicz, and Chaitin:In this note we present a natural example of a random numberthat goes beyond the class of omega-numbers. The idea goesback to Turing's celebrated paper On computable numbers,with an application to the Entscheidungsproblem [11],where he describes the computable numbers as the real numberswhose decimal expansion is calculable by nite means.According to Turing's denition, a number is computable its decimal expansion can be written down by a circle freemachine. This is a machine that performs an unendingcomputation in the course of machine to be circular. Circular machinesreach a conguration from which there is no possible move,or go on moving, but do not print any more symbols.SH: You might not want to call this an algorithm which hasa terminating clause, but it is a computable method. See 1) FinitenessKnuth, Vol. 1, Sec. 1.1:The modern meaning for algorithm is quite similar to that of_recipe_,_process_, _method_, _technique_, _procedure_, _routine_,_rigmarole_, except that the word algorithm connotes somethingjust a little different. Besides merely being a nite set ofrules that gives a sequence of operations for solving a specictype of problems, an algorithm has ve important features: 1) Finitness. An algorithm must always terminate after a nite number of steps. [...] (A procedure that has all of the characteristics of an algorithm except that it possibly lacks _nitness_ may be called a _computational method_. [...])(A procedure which has all the characteristics of an algorithm except that it possibly lacks nitness may be called acomputational method. Besides his algorithm for the greatestcommon divisor of two integers, Euclid also gave a geometrical construction that is essentially equivalent to algorithm E, except that it is procedure for obtaining the ``greatest common measure'' of the lengths of two line segments; this is a computational method that does not terminate if the given lengths are ``incommensurate''). [SH: for intererested constructivists] 2) Denitess. Each step of an algorithm must be precisely dened; the actions to be carried out must be rigorously and unambiguously specied for each case. [...] 3) Input. An algorithm has zero or more _inputs_: quantities that are give to it initially before the algorithm begins, or dynamically as the algorithm runs. [...] 4) Output. An algorithm has zero or more _outputs_: quantities that have a specied relation to the inputs. [...] 5) Effectiveness: An algorithm is also generally expected to be _effective_, in the sense that its operations must all be sufciently basic that they can in principle be done exactly and in a nite length of time by someone using pencil and paper. [...](A procedure which has all the characteristics of an algorithm except that it possibly lacks nitness may be called acomputational method. Besides his algorithm for the greatestcommon divisor of two integers, Euclid also gave a geometrical construction that is essentially equivalent to algorithm E, except that it is procedure for obtaining the ``greatest common measure'' of the lengths of two line segments; this is a computational method that does not terminate if the given lengths are ``incommensurate'').I think Church's (1937a) description agrees with innite symbols.The author [i.e. Turing] proposes as a criterion that an innitesequence of digits 0 and 1 be computable that it shall bepossible to devise a computing machine, occupying a nite spaceand with working parts of nite size, which will write down thesequence to any desired number of terms if allowed to run for asufciently long time. As a matter of convenience, certain furtherrestrictions are imposed on the character of the machine, but theseare of such a nature as obviously to cause no loss of generality -in particular, a human calculator, provided with pencil and paperand explicit instructions, can be regarded as a kind of Turing machine.The Broad Conception of Computation by Jack CopelandIs addition over the computable numbers a computablefunction? (That is, is x+y computable whenever x and yare both computable numbers?) The answer is .95yes', butoff the top of one's head one might think otherwise,for if x (or y) is a computable number having an innitedecimal representation, how can x be input, given Turing'srestriction that the input inscribed on the tape mustconsist of a nite number of symbols?The solution is to input x in the form of a program which,if inscribed on the (otherwise blank) tape of some universalTuring machine, would cause the machine to calculate thedecimal representation of x digit by digit. Nothing trickyis going on here. The program inscribed on the tape is, afterall, a sequence of symbols, and this particular sequence ofsymbols has no less a claim to be counted as a representationof the number, x, than .9514' and .951110' have to be counted asrepresentations of the number fourteen.In short, Turing has given us a new method for representingnumbers; and in this system there are nite representationsof some of the numbers which, in the decimal system, can berepresented only by means of an innite sequence of symbols.To return to the machine that is to add x and y, where x andy are any computable numbers: once the representations, inTuring's ingenious system, of x and y have been inscribed onthe tape, the machine is set in motion. First it calculatesthe rst digit of the decimal representation of x andremembers it; next it calculates the rst digit of therepresentation of y; then it adds these two digits, using aleft[CapitalEth]to[CapitalEth]right addition procedure; then it turns to the seconddigits of the representations, and so on. Each digit of thedecimal representation of x+y is produced by the machine insome nite number of steps.I hope the discussion so far has afforded some insight intowhat a computable number is, in Turing's restricted sense of'computable number'. A number is computable, in his sense,just in case the number can be expressed by means of a certainnite string of symbols, namely a string of symbols which, inscribed on the otherwise blank tape of some universal Turingmachine, will cause the machine to churn out the decimalrepresentation of the number.SH: I think this means that a TM can add Pi and e digit by digit.I posted not to argue on Russell's side, but because I thought thisTuring ingenuity deserved some recognition. I think the terminatingrequirement makes more sense when applied to a digital computer.I think there is one term. not halting, doing double duty for twodifferent reasons. Printing Pi can continue to output symbols, acircle-free machine, but a circular machine, can continue to movebut doesn't output symbols. So it is no longer a .95generative' case.BTW, Chaitin has a new, warm, e-book online about the historyand philosophy of developing primes, randomness and Omega.http://www.cs.auckland.ac.nz/CDMTCS/chaitin/ omega.htmlMETA MATH! The Quest for Omega by Gregory === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin message>> Michael N. Christoff message>>> This is the denition of a recursively enumerable language:>> This language is recursively enumerable. Given a string, x, thereexists> a> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is an>> innite string of 1's. The TM will not halt after a nite number of> steps.>>> You can't input an innite string to the tape. If you could, itwouldn't> > be a Turing machine.> No, but you can input nite instructions which generate innite output.> Russell is right about Turing saying this, and I found it repeated:>But that would be a different language. The language would then be { | Mis a TM that outputs a string a nite string of 1s}. This language isclearly undecidable. But that does not prove his point, as any languagewhere (language U lang_complement) is composed of arbitrary TMs and whosemembership is based on determining non-trivial properties of those TMs, isundecidable (a la Rice's theorem). However L is certainly decidable:Let me dene a language, L, that consists of all unary representations ofnatural numbers.1 = one, 11 = two, 111 = three, etc.l8r, Mike N. Christoff === Subject: Re: No Set Contains Every Computable Natural (was Church-Turing compared to Zuse-Fredkin thesis)Michael N. Christoff in> message>> Russell Easterly >> This is the denition of a recursively enumerable language:>> This language is recursively enumerable. Given a string, x, there> exists> a> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is an>> innite string of 1's. The TM will not halt after a nite numberof> steps.>>> > You can't input an innite string to the tape. If you could, it> wouldn't be a Turing machine.>>> No, but you can input nite instructions which generate inniteoutput.> Russell is right about Turing saying this, and I found it repeated:> But that would be a different language. The language would then be { |M> is a TM that outputs a string a nite string of 1s}. This language is> clearly undecidable. But that does not prove his point, as any language> where (language U lang_complement) is composed of arbitrary TMs and whose> membership is based on determining non-trivial properties of those TMs, is> undecidable (a la Rice's theorem). However L is certainly decidable:>> > Let me dene a language, L, that consists of all unary representations of> natural numbers.> 1 = one, 11 = two, 111 = three, etc.> l8r, Mike N. Christoff> You can't input an innite string to the tape. If you could, it> wouldn't be a Turing machine.>>Harris:> No, but you can input nite instructions which generate inniteoutput.> Russell is right about Turing saying this, and I found it repeated:Chaitin et al: This is a machine that performs an unendingcomputation symbols.[SH: If you read the thread, Russell previously claimed this.}Harris added in last post:I posted not to argue on Russell's side, but because I thought thisTuring ingenuity a TM and you respondedas if I supported Russell's argument and brought up languages,which I fail to see as germane to my informational post. Mymotive rests in the posts I've read on Google which have usedthis nite input stipulation to claim that a TM cannot generatea potentially innite output. But more to your point, I don't seewhy there can't be two inputs, x and y, a fragment of innite Pi(or any unique generic fragment) which is then nitely matchedagainst the potentially innite output of a Pi computational method.I think a mutual sequence match would eventually be discoveredalthough when this match would occur is undecidable. This is aspecualtive post on my part and I'm willing to change my === Subject: Re: No Set Contains Every Computable NaturalMichael N. Christoff dene a language, L, that consists of all unary representationsof> natural numbers.> 1 = one, 11 = two, 111 = three, etc.>> This language is recursively enumerable. Given a string, x, there existsa> TM that> will halt after a nite number of steps if x is a member of L.> This language is NOT decidable. Consider what happens if x is aninnite> string> of 1's. The TM will not halt after a nite number of steps.> You can't input an innite string to the tape. If you could, it wouldn't> be a Turing machine.This is equivalent to saying that a human operator must decide ifthe tape has an innite string of 1's before giving the tape to theTM. There is no automated way to decide if the tape has aninnite string of 1's.Requiring the input tape to be nite is a severe limitation.For example, no language, L, could contain every binaryrepresentation of rational numbers between 0 and 1.1/3 has an innite binary representation in base 2.Every denition of TM's that I have seen assumesthat an innite tape of blanks is allowed.> The set of all natural numbers is not a recursive set.> No natural number requires an innite unary representation. All may be> represented using a nite number of 1s.There is no TM that can decide if the string has aninnite string of 1's.> Consider what happens when we talk about the set of all TM's.> > Assume we can encode the state transition table of a TM using> a natural number. This set can not be recursive for the same> reason that the natural numbers are not recursive. Given a> string, i, we can not be sure that TM(i) is actually a TM> because we can not be sure that i is actually a natural number.> All Turing machines can be nitely represented. There is no such thingas> a TM transition function that requires an innite state automata for> representation.There is no TM that can decide if the transition table isinnitely long.> No set can contain every computable natural number.> >> Proof:> Assume a TM produces a tape with all of the natural numbers> encoded in unary where each natural is followed by a 0 (or a blank).>> This is impossible, a) a decider is limited to a nite number of steps> before halting, b) to output all integers in unary requires an inifnite> number of steps - hence, no TM can produce this output.>> Turing gives the state transition table of such a TM> 010110111011110...Turing's TM doesn't produce a unary representation of every natural?> I can dene a three state TM that willfind a natural number> that is not on this tape:>> 1) Read right until there is a 0.> 2) Read right until a second 0 is found.> 3) Backup and write a 1 on the previous 0.> Repeat steps (1) through (3).>> This TM will always produce a tape that has exactly one 0.> This 0 will be at a nite position on the tape and the string of 1's> > that preceds this 0 represents a natural number that was not on> the original input tape.> You have not at all proven this. First, how can there be a 0 at a nite> position from the start? If there is, there must a 0 to its right (infact> an innite number of zeros), hence step 2 will read this second zero, and> step 3 will go back and erase the .95remaining 0'. The part about thenumber> preceding the last 0 being an integer not on the tape makes no senseeither.Is doesn't matter that there are an innite number of 0's on the inputtape.Every 0 on the original input tape is in a nite position.The TM I describe will produce an output tape with exactly one 0.My TM doesn't ever write a 0, so the 0 was on the input tape.> The Halting Problem is ill posed.> There is no set that contains every TM>> Sure there is : A = { | M is a valid TM representation}It is impossible to decide if M is a valid representation.> It is easy to check, given a data structure, whether the input is a validTM> or not.It is impossible for a TM to decide if M is a valid representation.> just as there is no set> that contains every computable natural number.> > All natural numbers are computable. However, they _all_ can't begenerated> in a single run of any algorithm/TM.The output of a TM can't contain a representation of every natural?> Now, about the difference between nite amount of time vs> nite number of steps. There are theories of computing where> a TM can perform an innite number of steps in nite time.> These are called hypercomputers.> http://en.wikipedia.org/wiki/Hypercomputer>> A non-deterministic Turing machine is an example of a hypercomputer.>> No, an NTM is not a hyper-computer since any NTM can be simulated by a> standard TM. The NTM must be given additional abilities to become> super-Turing.I misread the examples given at wikipedia. It says:A non-deterministic Turing machine which has a preference ordering over itsnal states.The additonal ability is preference ordering over its nal states.> Another example is an accelerated Turing Machine. An ATM performs> the rst operation in one unit of time, the second operation is 1/2unit> of time, the third operation in 1/4 unit of time, etc. An ATM willperform> an innite number of operations after two units of time.>> Assume we have a computer that can perform an operation in one> nanosecond. The language, L, that I dened above is not even> recognizable if we expect an answer before the universe freezes over.> We can easily compute a natural number, n, that is so large that> our nanosecond computer will take 15 billion years to recognize> n as a natural number. There is only a nite number of naturals> less than or equal to n. There is an innite number of naturals> larger than n. Nearly all natural numbers are larger than n.>> So, we see that we have to assume that a TM can perform> an innite number of operations in nite time to even say> that L is recursively enumerable.> To say that there is some natural number that a physical computer willnever> be able to print out in unary is one thing, but to say that a TM (a purely> mathematical object) .95can't' print out certain natural numbers in unary ina> nite number of steps is not correct.I didn't say that a TM can't print out certain natural numbers.I said that a TM that requires a xed, nite amount of time toperform an operation can't print certain natural numbers in areasonable amount of time.Russell- The universe is one dimensional