mm-297 === Subject: Re: Antidiagonal, Infinity >What I propose is that given any >rational that the value greater than it and less than any other >greater is irrational, There is no such number, as several different people have shown you. > In non-standard analysis, there might be, however. > See Alain Robert's book about NSA. Rather than being > irrational, it would be non-standard, though. I have yet to see any standard or non-standard model of the reals in which there is a smallest positive number. In the various non-standard versions, there tend to be rather more numbers between any positive number x and zero, there are all those y such that y/x are ifinitesimal but positive, then all those z such that z/y is infinitesimal but positive, and so on ad infinitum. === Subject: Re: Antidiagonal, Infinity >What I propose is that given any >rational that the value greater than it and less than any other >greater is irrational, There is no such number, as several different people have shown you. In non-standard analysis, there might be, however. > See Alain Robert's book about NSA. Rather than being > irrational, it would be non-standard, though. > I have yet to see any standard or non-standard model of the reals in > which there is a smallest positive number. Who says that that is meant? In nsa, there can be a nonstandard number that can be said to be 'greater than (a given standard rational) and less than any other (standard) greater' That it is not unique, who cares? In nsa, though, there are both rational and irrational non-standard numbers with this property. So, the statement that such values are necessarily irrational is not true, there. But who knows what this poster's intuition may eventually lead to? Herman Jurjus === Subject: Re: Antidiagonal, Infinity >What I propose is that given any >rational that the value greater than it and less than any other >greater is irrational, There is no such number, as several different people have shown you. In non-standard analysis, there might be, however. > See Alain Robert's book about NSA. Rather than being > irrational, it would be non-standard, though. I have yet to see any standard or non-standard model of the reals in > which there is a smallest positive number. > Who says that that is meant? > In nsa, there can be a nonstandard number that can be said to be > 'greater than (a given standard rational) and less than any other (standard) > greater' > That it is not unique, who cares? Ross wants to use non-standard numbers to confirm his hypothesis that there is a next real after any real, and that the irrationals and rationals alternate on the real line or on some non-standard real line. So he cares. On the other hand, his hypothesis is way out in left field, where he has been stuck for months, if not years. === Subject: Re: Antidiagonal, Infinity (On RAF) > But who knows what this poster's intuition may eventually lead to? We should all worry :-( -- === Subject: Re: Antidiagonal, Infinity >What I propose is that given any >rational that the value greater than it and less than any other >greater is irrational, There is no such number, as several different people have shown you. > In non-standard analysis, there might be, however. > See Alain Robert's book about NSA. Rather than being > irrational, it would be non-standard, though. > I have yet to see any standard or non-standard model of the reals in > which there is a smallest positive number. > In the various non-standard versions, there tend to be rather more > numbers between any positive number x and zero, there are all those > y such that y/x are ifinitesimal but positive, then all those z such > that z/y is infinitesimal but positive, and so on ad infinitum. Between any two odd integers is an even integer, between any two even integers is an odd integer. The density in their union of either is one half. Here I equate density with measure in the unit interval. I don't care if you ignore gravity, it won't do you much good, I'm here only concerned with considering a model where the rationals and irrationals alternate in the reals. If there are more irrationals than rationals and rationals and irrationals are disjoint and distinct, then, where they are each totally ordered, then there necessarily would be irrationals with no rationals between them. Yet, there are not. I'm trying to think of a function between the unit interval's reals and irrationals. The claim is that one exists because the rationals map onto the integers and the integers don't map to the reals, thus that the irrationals map onto the reals else the reals would be a union of two sets that don't map onto the reals. Yet, a construction explicitly mapping each element of the irrationals to each element of the reals is not given. I'm also still looking for a mapping between R[0,1)^N and R[0,1). I like to think that the rationals and irrationals alternate and that the function f(x)=x+iota maps Q[0,1) onto P(0,1), and f(x)=x-iota maps Q(0,1] to P(0,1). Then again I think the impulse function evaluates to half infinity at zero, and consider the Gamma function on negative integers to have values of various finite multiples of a scalar infinity. Now I'm looking at the post about mapping R <-> P. I don't immediately grasp vector space over a field and linearly independent. You have the sequence b being a sequence of reals each linearly independent over Q, and a set C of reals of {b_0, b_1, ...} linearly independent over Q, with the initial sequence element b_0 being a rational. RQ=P, you claim that R injects into P by f(b_n)=b_{n+1} and f(c)=c. Why do you have braces around n+1 instead of parentheses? Then you have F(c)=c, for c in C. I think you mean that c in C is not an element of the sequence b. Then you say to extend that to all of R by linearity over Q. So you claim a function f(r)=p for r in R and p in P to be defined for all reals. What's r for f(r)=pi? What's p for f(2)? Why f and F, presumably a shift-key error? http://mathworld.wolfram.com/LinearlyIndependent.html http://mathworld.wolfram.com/VectorSpace.html http://www.wikipedia.org/wiki/Vector_space: A set V is a vector space over a field F, if given an operation vector addition defined in V, deno v+w for all v, w in v, and an operation scalar multiplication in V, deno a*v for all v in V and a in F, the following 10 properties hold for all a, b, in F and u, v, and w in V: 1. v+w E V 2. u+(v+w) = (u+v)+w 3. v+0 = v 4. v-v = 0 5. v+w = w+v 6. a*v E V 7. a*(b*v) = (a*b)*v 8. 1*v=v 9. a*(v+w) = a*v + a*w 10. (a+b)*v = a*v + b*v Those each hold for V = R and F = Q. Properties 1 through 5 indicate that V is an abelian group under vector addition. The intersection of all subspaces containing a given set of vectors is called their span; if no vector can be removed without diminishing the span, the set is called linearly independent. So you say each element of the sequence represents a set of vectors or a set of a vector, I'm not sure which, and that it is linearly independent over Q because removing that vector from the set of vectors would diminish the span of the intersection of the subspaces of the vector space. Please neaten that up provide a more self-contained explanation. Also explain. While you're at it show a bijection between R^N and R. Some talk here is about the nosntandard treatment of the reals: the hyperreals. One thing to note is that *R, the hyperreals, as a set contains the same elements as R, the reals. It's just a different way to consider them. About the uniform probability distributions over intervals of reals, that's not about making some new definition of what a probability distribution is. It's about applying the characteristics of a probability distribution to an infinite population. We were talking about the probability of an infinite binary seqence having one element being on, the rest off. That probability is expressed as n/2^n, as n diverges to infinity. The probability of any possible sequence is equal to 2^n/2^n, in the limit: one. So anyways out of those n possible sequences with one on bit and the rest off bits, each is equally probable. The probability of each among all possible infinite binary sequences is being1/2^n, the probability of each among all infinite binary sequences with one on bit is 1/n. So a theoretical (read: thought experiment) method to generate an element of N is to once again flip infinitely many coins. At this point it's a crazy, or rather, unconventional thought experiment in that the first coin toss says whether it is oo/2 or greater or less than oo/2. Assume it's a long sequence of zeros, then it would be saying about whether the result is greater than or equal to oo/4, oo/8, oo/16, etcetera. Without a method to generate a sample from a uniform distribution over the natural numbers, it's still that the probability of selecting any is 1/|N|. Of course that's ludicrous but at the same time it allows us to consider the realm of thought in concern of this issue and to then talk about the probability of selecting a given element of the natural integers assuming a uniform probability distribution over the integers. At least we seem to have some agreement that a uniform probability distribution over an interval of the reals exists, and a simple method to sample an element of an interval of the reals exists. infinitesimals, it talks about 1-infinitesimals, 2-infinitesimals, etcetera, n-infinitesimals, with the oo-infinitesimal being zero. Ross === Subject: Re: Antidiagonal, Infinity > Between any two odd integers is an even integer, between any two even > integers is an odd integer. The density in their union of either is > one half. What does that last sentence mean? > Here I equate density with measure in the unit interval. Then the integers have density zero. > I don't care if you ignore gravity, it won't do you much good, I'm > here only concerned with considering a model where the rationals and > irrationals alternate in the reals. Which is still as stupid as trying to ignore the law of gravity. > If there are more irrationals than rationals and rationals and > irrationals are disjoint and distinct, then, where they are each > totally ordered, then there necessarily would be irrationals with no > rationals between them. Yet, there are not. In the set of rationals, there are no irrationals. In the set of irrationals, there are no rationals. In the set of reals, there are countably many rationasl ans uncontably many reals arranged so that between any two distinct reals there are countably many rationals and uncountably many reals. In fact, there is a order preserving bijection from any open interval, (a,b), with a < b, to the set of all reals, namely f:(a,b) -> R: x |-> (a-b)*x/[(x-a)*(x-b)], and if a and b are rational, the mapping f carries rationals to rationals and irrationals to irrationals. > I'm trying to think of a function between the unit interval's reals > and irrationals. The claim is that one exists because the rationals > map onto the integers and the integers don't map to the reals, thus > that the irrationals map onto the reals else the reals would be a > union of two sets that don't map onto the reals. Yet, a construction > explicitly mapping each element of the irrationals to each element of > the reals is not given. I'm also still looking for a mapping between > R[0,1)^N and R[0,1). A reverse bijection, from the reals to the irrationals, was given in at least 2 versions in a prior posting in this thread, so just take the inverse bijection of either of them. > I like to think that the rationals and irrationals alternate and that > the function f(x)=x+iota maps Q[0,1) onto P(0,1), and f(x)=x-iota maps > Q(0,1] to P(0,1). You may like to think a lot of things, but that does not make them true. > Then again I think the impulse function evaluates to half infinity > at zero, and consider the Gamma function on negative integers to have > values of various finite multiples of a scalar infinity. Again you reveal that your wiring is short circui. > Now I'm looking at the post about mapping R <-> P. I don't > immediately grasp vector space over a field and linearly > independent. You have the sequence b being a sequence of reals each > linearly independent over Q, and a set C of reals of {b_0, b_1, ...} > linearly independent over Q, with the initial sequence element b_0 > being a rational. RQ=P, you claim that R injects into P by > f(b_n)=b_{n+1} and f(c)=c. Why do you have braces around n+1 instead > of parentheses? Standard newsnet notation for a compound subscript. Then you have F(c)=c, for c in C. I think you mean > that c in C is not an element of the sequence b. Then you say to > extend that to all of R by linearity over Q. So you claim a function > f(r)=p for r in R and p in P to be defined for all reals. What's r > for f(r)=pi? What's p for f(2)? Why f and F, presumably a shift-key > error? > http://mathworld.wolfram.com/LinearlyIndependent.html > http://mathworld.wolfram.com/VectorSpace.html > http://www.wikipedia.org/wiki/Vector_space: > A set V is a vector space over a field F, if given an operation > vector addition defined in V, deno v+w for all v, w in v, and an > operation scalar multiplication in V, deno a*v for all v in V and a > in F, the following 10 properties hold for all a, b, in F and u, v, > and w in V: > 1. v+w E V > 2. u+(v+w) = (u+v)+w > 3. v+0 = v > 4. v-v = 0 > 5. v+w = w+v > 6. a*v E V > 7. a*(b*v) = (a*b)*v > 8. 1*v=v > 9. a*(v+w) = a*v + a*w > 10. (a+b)*v = a*v + b*v > Those each hold for V = R and F = Q. > Properties 1 through 5 indicate that V is an abelian group under > vector addition. > The intersection of all subspaces containing a given set of vectors > is called their span; if no vector can be removed without diminishing > the span, the set is called linearly independent. > So you say each element of the sequence represents a set of vectors or > a set of a vector, I'm not sure which, and that it is linearly > independent over Q because removing that vector from the set of > vectors would diminish the span of the intersection of the subspaces > of the vector space. I have this set of reals B = {b_0,b_1,b_2, ....} whose members are are, as vectors over Q, linearly independent and so that b_0 is a non-zero rational. Every real in span(B) is a linear combination of finitely many of the members of B. There are other reals which are linearly independent of the span of B, the set of which I called C, and which is a (vector) subspace of R. Given any real r, then there are unique rationals p,q, and a unique real b in span(B) and a unique real c in C such that r = p*b+q*c. Thus R is the direct sum of subspaces span(B) and C. It may be proven that there is only one Q-linear function, say f, from R to RQ and such that f(b_0) = b_1, f(b_1) = b_2 etc., and f(c) = c for every c in C. This function is a bijection. > Please neaten that up provide a more self-contained explanation. Also > explain. While you're at it show a bijection between R^N and R. The explanation is sufficient for those who know a little math. Learn a bit about vector spaces and it may become clear to you, or don't and it won't. > Some talk here is about the nosntandard treatment of the reals: the > hyperreals. One thing to note is that *R, the hyperreals, as a set > contains the same elements as R, the reals. It's just a different way > to consider them. The Robinson formulation of *R has more than a single member corresponding to a member of R, it has uncountably many coresponding to eanc member of R, which are infinitesimally close to each other, as well as some which do not correspond to any member of R. > About the uniform probability distributions over intervals of reals, > that's not about making some new definition of what a probability > distribution is. It is well known, to those who understand what pdf's (probability density functions) are that there cannot be a uniform pdf on R. Uniform pdf's require finite real intervals or finite sets to operate on. You cannot make one on a countably infinite set nor on an unbounded real interval. > It's about applying the characteristics of a > probability distribution to an infinite population. Since a uniform pdf must have certain properties to be a pdf, there are limits on what sets they can exist on, and N, Q and R are outside those limits. [garbage dele] > Of course that's ludicrous but at the same time it allows us to > consider the realm of thought in concern of this issue and to then > talk about the probability of selecting a given element of the natural > integers assuming a uniform probability distribution over the > integers. At least we seem to have some agreement that a uniform > probability distribution over an interval of the reals exists, and a > simple method to sample an element of an interval of the reals exists. We have no agreement that such a distribution exists, because it cannot. > infinitesimals, it talks about 1-infinitesimals, 2-infinitesimals, > etcetera, n-infinitesimals, with the oo-infinitesimal being zero. Your knowledge of infinitesimals is nil. Until you get a reasonable understanding of the standard reals, your hopes of understanding anything about non-standard reals is unreal. === Subject: Re: Naive Q: Set theory, logic - which comes first? <1xUcb.14254$O85.6040@pd7tw1no> <3f79e264$7$fuzhry+tra$mr2ice@news.patriot.net> at 01:50 PM, mattias_wikst71@hotmail.com (Mattias Wikstr?m) said: >G.9adel did not show this. He showed that for a given sound formal >system in which the statements about natural numbers can be >formula, there are statements that can neither be proven nor >disproven. Google for G.9adel number. He represen statements as natural numbers. The theorems he proved about statements were also theorems about the integers representing them. -- Shmuel (Seymour J.) Metz, SysProg and JOAT Unsolici bulk E-mail will be subject to legal action. I reserve the right to publicly post or ridicule any abusive E-mail. Reply to domain Patriot dot net user shmuel+news to contact me. Do === Subject: Re: Grid: Integers = To Sum Of Some Divisors > Take an n-by-n-grid, n>= 3. Place the integers 2 to (n^2 +1) into the grid, > one DISTINCT integer per grid-square, so that: If s(k,j) = a grid-square (ie. an element of an > n-by-n matrix), then > (for all k and j where n >= k >= 3 and n >= j >= 1) > s(k,j) = (any divisor >= 2 of s(k-1,j)) + > (any divisor >= 2 of s(k-2,j)), and> (for all k and j where n >= k >= 1 and n >= j >= 3) > s(k,j) =(any divisor >= 2 of s(k,j-1)) + > (any divisor >= 2 of s(k,j-2)) >[...] an n=3 example is: > 5 3 8 > 2 6 4 > 7 9 10 > Is there an n=4 example?? There appear to be 2 basic solutions and of course their transposes: 5 2 7 9 3 12 6 15 8 4 10 14 11 16 13 17 5 3 8 11 2 12 4 16 7 6 10 13 9 15 14 17 11 2 13 15 3 12 6 9 14 4 16 8 5 10 7 17 11 3 14 5 2 12 4 10 13 6 16 7 15 9 8 17 which a bit iously could be extended to 5x5 or 6x6 but not much further because it uses nes for loops, one level per cell, rather than a recursive approach. The program takes about 1 second to exhaust the 4x4 case. -jiw === Subject: Re: Grid: Integers = To Sum Of Some Divisors > Take an n-by-n-grid, n>= 3. Place the integers 2 to (n^2 +1) into the grid, > one DISTINCT integer per grid-square, so that: If s(k,j) = a grid-square (ie. an element of an > n-by-n matrix), then > (for all k and j where n >= k >= 3 and n >= j >= 1) > s(k,j) = (any divisor >= 2 of s(k-1,j)) + > (any divisor >= 2 of s(k-2,j)), > and> (for all k and j where n >= k >= 1 and n >= j >= 3) > s(k,j) =(any divisor >= 2 of s(k,j-1)) + > (any divisor >= 2 of s(k,j-2)) >[...] an n=3 example is: > 5 3 8 > 2 6 4 > 7 9 10 Is there an n=4 example?? > There appear to be 2 basic solutions and of course their transposes: > 5 2 7 9 > 3 12 6 15 > 8 4 10 14 > 11 16 13 17 > 5 3 8 11 > 2 12 4 16 > 7 6 10 13 > 9 15 14 17 > 11 2 13 15 > 3 12 6 9 > 14 4 16 8 > 5 10 7 17 > 11 3 14 5 > 2 12 4 10 > 13 6 16 7 > 15 9 8 17 > which a bit iously could be extended to 5x5 or 6x6 > but not much further because it uses nes for loops, > one level per cell, rather than a recursive approach. > The program takes about 1 second to exhaust the 4x4 case. > -jiw Ahh...So there ARE solutions after all! I was neglecting the likelyhood of bigger integers, such as the 11 and 12, being in the upper-left, perhaps. Leroy Quet === Subject: Re: Deep Thoughts # 1: A new limitation to the human mind > 1. Mathematics is the science in which we make something out of > nothing. > Wrong. Mathematics is built on the 13 Axioms, which are not nothing. And where did those 13 axioms come from? What is needed to develop them? > 2. All of man-made Mathematics consists of an abstraction from > physical processes. > Wrong again. Mathematics consists of theorems deriva by following a > set of formal rules. And when is this not just an abstraction from physical processes (example, please)? > 3. Since Mathematics in general needs nothing to be crea, then the > human mind seems to be limi in that it can only consider > possibilities that are analogous to physical processes. > Well, I think first of all mathematics exist all by themselves, as a > logical system. And so needs nothing to be crea. > However one may argue that for humans this exists in > its precise own way, because the human mind works the way it works. That's right. Exactly. And in particular, the human mind seems to only discover the mathematics that is an abstraction from physical processes. > Thus mathematics actually may help delineate the limits of the human > mind. That is exactly what I am postulating. Cambridge, MA === Subject: Re: Deep Thoughts # 1: A new limitation to the human mind 7e3Z2dkQEBC5ubm60r3HAAACeUlEQVR4nIXTQW+ bMBQAYChLfcWzUq5pipUr7lPptUNGXBMC8zUZ qnt1aNz392c7pGXSpvkSyV/ee37POFr/Y0X/g56rxd+ gb2IQC8X79brdLtovaBgACIsRMVTr4hN4 Ah54xy0rtdbjFRCAupizIhUDB69X2IHAGKCrxyrxcJyA76CQKwZn2ckEXK6h/ YwoOld/zJUMEYds ghMIYhj0kjehxqGYFacgalk1PpM+jBOkvg0othFR4bjDVHyjQx+FZ+ b29fMEe114SIC6UB/RXoCX enAhGQORAdxp/TaN5N63lNqGJZACO2n9/ QL81qfVQjEXAkBKPyoPm7BfPqFLJ0qBt1fwmfTAFiYW MbAC1WmCnyEitcYImtI07fY3FwglBuwMUiqoiLv98gL+ 4PrNSmXdWGJK7Q4D8JBpWeXGxi6CpqOJ QoOrkOksKzMaRinN7LsI8OChsGOl+ogiE8SeaIAP9/ 9BRIs1xzgzESWteQ7gDgWQpmRdmcgtNFYJ / 5W4CWpRRsTyHE2UBgifjzvUQMGMOfYYO1CI7wFWfhwsWXSNq0qQcMQkgBvhADvI rOrduRArpW7D Rflb0gjHvO5kpUhX93h3DJ3v9VB+S8pMulW1kis73aAqh/ LpBYalbA2qiLZKP16G+KHLowIYojSm UTys+/ LrogaFVFTKpN2P45qT6UX58qrbEFcil81h9tQSfVSyIZ0v3zzNYEMPVtbR2e3XL 8v547w/ uDymk7wfXx7n8PBscrm1fW/G1a8/gKiz3GJeYbt5ncMJ+ Y1ckVxi19zMwaIcXXUreb6yc1gQ9ypr tLKSCueQjQ4qxFzKXo0zwNDbxv/U2ynkN+Dj/u9oA6vhAAAAAElFTkSuQmCC >> 1. Mathematics is the science in which we make something out of >> nothing. > Wrong. Mathematics is built on the 13 Axioms, which are not nothing. Which 13? -- And yes, for those who think that just maybe I did find a short proof of Fermat's Last Theorem, and THE prime counting function, if I succeed at what I'm working on now world economy as you know it will be gone. -- branches out. === Subject: Re: Deep Thoughts # 1: A new limitation to the human mind >> 1. Mathematics is the science in which we make something out of >> nothing. Wrong. Mathematics is built on the 13 Axioms, which are not nothing. > Which 13? I am sorry, I let myself get carried away by indignation. I would have to look them up. My math has become extremely rusty since I studied, but I can recall that our first semester analysis class consis in laying out the foundation of mathematics by learning 23 axioms and how they sufficed to build up the rest. I believe we star with the peano Axioms. === Subject: Re: Deep Thoughts # 1: A new limitation to the human mind >> 1. Mathematics is the science in which we make something out of >> nothing. Wrong. Mathematics is built on the 13 Axioms, which are not nothing. > Which 13? > -- > And yes, for those who think that just maybe I did find a short proof > of Fermat's Last Theorem, and THE prime counting function, if I > succeed at what I'm working on now world economy as you know it will > be gone. -- branches out. There is a guy who is really a fundamentalist religious preacher calling himself Paniagua (Bread 'n water) He got nicknamed something like Taco Bill. I hope this is not the same guy!! Bob Pease === Subject: Re: Deep Thoughts # 1: A new limitation to the human mind > There is a guy who is really a fundamentalist religious preacher calling > himself Paniagua (Bread 'n water) > He got nicknamed something like Taco Bill. > I hope this is not the same guy!! > Bob Pease No, Im not, that is my name. I am religious, but neither am I a preacher nor am I a fundamentalist. Just wan to mention that Springer-Verlag's annual mathematics book sale, the Yellow Sale, is finally back. Here's the URL: http://www.springer-ny.com/yellowsale/ The book sale is available in bookstores across North America, as well as online at the URL above to customers in the Americas. Springer is the world's leading publisher in the field of mathematics. Jason Roth Springer-Verlag NY === Subject: irreducible polynomial ? Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each positive integer k? If so, how is it proved? --Jim Buddenhagen ------------ To reply copy jbuddenh@REMOVEtexas.net to address bar and edit out REMOVE === Subject: Re: irreducible polynomial ? I asked: > Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each > positive integer k? If so, how is it proved? I received email from Joe Silverman answering this question and giving a good deal of additional information on the factorization of Chebeshev polynomials. --------------------------------------------------------------- Comments from Joe Silverman: The n'th Chebeshev polynomial (up to factors of 2 used by different authors) is the polynomial F_n(x) with the property that F_n(2*cos(t)) = 2*cos(n*t). So if we put t = arccos(x/2), then we get F_n(x) = 2*cos(n*arccos(x/2)). This is your formula. If we write cos(t) = (e^{it} + e^{-it})/2, and for ease of notation, let z = e^{it}, then we get F_n(z+z^{-1}) = z^n + z^{-n}. This is another characterization of F_n. The roots of F_n(x), from your formula or from this alternative, are x = 2*cos(pi*(j+1/2)/n) for j = 0,1,2,...,n. Notice this can also be written as x = e^{it} + e^{-it} with t = (pi*(j+1/2))/n. it's easy to see that the splitting field of F_n(x) is the real subfield of the 4n'th cyclotomic field. In other words, the roots of F_n(x) generate the field K_{4n} = Q(e^{pi*i/2*n}+e^{-pi*i/2*n}). The degree of this field is [K_n:Q] = phi(4*n)/2, where phi(n) is Euler's phi function. On the other hand, the degree of F_n is n. So the conclusion is the following: Proposition: F_n(x) is irreducible over Q if and only if phi(4*n) = 2*n. The case you're asking about is n = 2^k, and indeed phi(4*2^k) = phi(2^{k+2}) = 2^{k+1} = 2*2^k, so your polynomials are irreducible. Further, I think this is probably the only case that phi(4*n) = 2*n, so the only case that F_n is irreducible. Hope this is of some help. Feel free to post this, if you want. ------------------------------------------------------ --Jim Buddenhagen To reply copy jbuddenh@REMOVEtexas.net to address bar and edit out REMOVE === Subject: Re: irreducible polynomial ? > I asked: > Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each > positive integer k? If so, how is it proved? > I received email from Joe Silverman answering this question > and giving a good deal of additional information on the > factorization of Chebeshev polynomials. > --------------------------------------------------------------- > Comments from Joe Silverman: > The n'th Chebeshev polynomial (up to factors of 2 used by different authors) > is the polynomial F_n(x) with the property that > F_n(2*cos(t)) = 2*cos(n*t). > So if we put t = arccos(x/2), then we get > F_n(x) = 2*cos(n*arccos(x/2)). > This is your formula. > If we write cos(t) = (e^{it} + e^{-it})/2, and for ease of notation, > let z = e^{it}, then we get > F_n(z+z^{-1}) = z^n + z^{-n}. > This is another characterization of F_n. > The roots of F_n(x), from your formula or from this alternative, are > x = 2*cos(pi*(j+1/2)/n) for j = 0,1,2,...,n. > Notice this can also be written as > x = e^{it} + e^{-it} with t = (pi*(j+1/2))/n. > it's easy to see that the splitting field of F_n(x) is the real subfield > of the 4n'th cyclotomic field. In other words, the roots of F_n(x) > generate the field > K_{4n} = Q(e^{pi*i/2*n}+e^{-pi*i/2*n}). > The degree of this field is [K_n:Q] = phi(4*n)/2, where phi(n) is Euler's > phi function. On the other hand, the degree of F_n is n. So the conclusion > is the following: > Proposition: F_n(x) is irreducible over Q if and only if phi(4*n) = 2*n. > The case you're asking about is n = 2^k, and indeed > phi(4*2^k) = phi(2^{k+2}) = 2^{k+1} = 2*2^k, > so your polynomials are irreducible. Further, I think this is probably the > only case that phi(4*n) = 2*n, so the only case that F_n is irreducible. > Hope this is of some help. Feel free to post this, if you want. by essentially the same argument you see that the odd chebyshev polynomials of prime order are irreducible if you eliminate the trivial factor x (zero x=0) sincerely Klaus > ------------------------------------------------------ > --Jim Buddenhagen > To reply copy jbuddenh@REMOVEtexas.net to address bar and edit out REMOVE === Subject: Re: irreducible polynomial ? > Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each > positive integer k? If so, how is it proved? and the proof is essentially trivial: Each polynomial is the square of its predecessor less 2. This follows immediately from the identity (cos z)^2 = (1 + cos(2*z))/2. Now for k=0,1 the polynomials are x and x^2-2 so it is clear that for each k the leading coeff is 1, the constant is 2 and all other coeffs are even, so Eisenstein applies as Arturo suggests. --Jim Buddenhagen === Subject: Re: irreducible polynomial ? http://icm.mcs.kent.edu/reports/1998/ICM-199802-0001.pdf === Subject: Re: irreducible polynomial ? Isn't it something like Chebychev polynomial? === Subject: Re: irreducible polynomial ? Visiting Assistant Professor at the University of Montana. >Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >positive integer k? If so, how is it proved? Is it a polynomial? In what? Irreducible over what? === Subject: Re: irreducible polynomial ? >Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >positive integer k? If so, how is it proved? this is up to normalization the n-th (=2^k) chebyshev polynomial (for |x|<=2) http://mathworld.wolfram.com/ ChebyshevPolynomialoftheFirstKind.html its roots are rela to the n-th roots of unity, and the irreducibility to the special value of phi(n) hth (and hope it is not nonsense) klaus > Is it a polynomial? In what? Irreducible over what? It's not denial. I'm just very selective about > what I accept as reality. > --- Calvin (Calvin and Hobbes) > magidin@math.berkeley.edu === Subject: Re: irreducible polynomial ? >Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >positive integer k? If so, how is it proved? > Is it a polynomial? In what? Irreducible over what? in x, irreducible over Q For example, 2*cos(2^4*arccos(x/2)) = 16 14 12 10 8 6 4 2 x - 16 x + 104 x - 352 x + 660 x - 672 x + 336 x - 64 x + 2 is irredicible. === Subject: Re: irreducible polynomial ? Visiting Assistant Professor at the University of Montana. >>Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >>positive integer k? If so, how is it proved? >> Is it a polynomial? In what? Irreducible over what? >in x, irreducible over Q >For example, >2*cos(2^4*arccos(x/2)) = > 16 14 12 10 8 6 4 2 >x - 16 x + 104 x - 352 x + 660 x - 672 x + 336 x - 64 x + 2 >is irredicible. Never seen that before; but would it not be possible to prove it irreducible by using Eisenstein's Criterion? Looks like the leading coefficient is 1, the constant coefficient is 2, and all the other terms have even coefficient. If the pattern holds for arbitrary k, then there you are. === Subject: Re: irreducible polynomial ? >Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >>positive integer k? If so, how is it proved? >Is it a polynomial? In what? Irreducible over what? >>in x, irreducible over Q >>For example, >>2*cos(2^4*arccos(x/2)) = >>16 14 12 10 8 6 4 2 >>x - 16 x + 104 x - 352 x + 660 x - 672 x + 336 x - 64 x + 2 >>is irredicible. > Never seen that before; but would it not be possible to prove it > irreducible by using Eisenstein's Criterion? Looks like the leading > coefficient is 1, the constant coefficient is 2, and all the other > terms have even coefficient. If the pattern holds for arbitrary k, > then there you are. Right you are. Let p_k(x) = cos(2^{k} * arccos(x/2)), then p_1(x) = x^{2} / 2 - 1 and p_{k+1}(x) = 2 * (p_k(x))^2 - 1 in x^2, has constant term equal to 2 or -2 and that 2p_k(1) = -1 and 2p_k(2) = 2. As you say, there you are. You don't even need to invoke Eisenstein. Rick === Subject: Re: irreducible polynomial ? >Is the polynomial 2*cos(2^k*arccos(x/2)) irreducible for each >positive integer k? If so, how is it proved? > Is it a polynomial? In what? Irreducible over what? Yes. In x. Over Z or Q. --JB === Subject: Re: MTL and MatLab iQBVAwUAP4MJpEHMCo9UcraBAQEGZgH/WYWzR/ 00hb6naqYilcbwMgCo3o9rDreJ mEK3cJTjmuxifF+wuAqYurB6n2KECVpTlR7nLnRfEDHEXqXCt6tWuA== =Gqcd > Hello! > I am trying to make Matrix Template Library > (http://www.osl.iu.edu/research/mtl/) interact with MatLab 6.5. If > anybody has done it, please give me your comments on what you think > about it. I would greatly appreciate it! > Iryna I have used both. What do you mean by having MTL 'interact' with Matlab? Do you want to call matlab functions via the mex interface? Or do want to generate a C++ program that is callable from matlab? I recently did a project where results had to be read in Matlab, but the simulation which generates them is far too complex to run efficiently as a Matlab program. I crea a class for results that allowed easy measurments from a simulation, and automates the writing of a corresponding mat file. If this is what you are trying to do, let me know and I can send you the code (I have a version on the web, but it needs to be upda). Regarding MTL... It's been a long time since any updates came from MTL? In fact he object orien numerics websit (oon.org) is looking a bit out of date. Is there a better reference? Has anything to replace blitz or MTL come out ? G.S. [ See http://www.gotw.ca/resources/clcm.htm for info about ] [ comp.lang.c++.modera. First time posters: Do this! ] === Subject: Re: Brownian motion approximation Can you spell out how to do it? I can see that the general theorem follows easily if you can prove it where f(t) is a linear function(by scaling, Markov property, etc.) but how do you show easily that f(t) is approxima when f is linear? As I mentioned, I can handle the case f(t)=0 for all t, because then you can use the reflection principal. Is B_t - f(t) with f linear a BM with drift(I have heard the term before but don't really know what it is)? >> A while back I pos a question about whether or not > P[sup_{0<=t<=1}|B_t - f(t)| < d] > 0 for all d > 0 and f(t) continuous >> on [0,1] with f(0) = 0. > In other words, does Brownian motion uniformly approximate any >> continuous function(with f(0)=0) with positive probability? Someone >> replied that it does, and this follows from first proving it for f(t) >> = 0 for all t and then applying the Cameron-Martin Theorem. I can do >> it for f(t)=0, but I don't seem to be able to find a reference for the >> Cameron-Martin Theorem, though it seems to be rela to Girsanov's >> Theorem, and maybe even follows from it. Can someone give me some help >> or lead me to a reference? I don't believe there is any significant difference between the >Cameron-Martin-Girsanov theorem, the Girsanov theorem and the Cameron-Martin >theorem. As I understand it the same theorem was discovered independently >and is now attribu to all three. Rather like the Green-Gauss-Ostrogradsky theorem. > This does not need quoting any complica theorems. Construct > a polygonal function h such that |f - h| < d/3 on the interval, > bound (from below) the probability that |B_t - h(t)| < d/3 at > all vertices, and bound the probability that B differs by d/3 > from its polygon at those vertices. The Markov nature of B and > the boundedness and continuity of f enable all of this to be > carried out easily. === Subject: Vedctor Calculus Question Could someone help me to understand how to find the minimum distance between a surface (say f1(x,y,z)=c1) and a line (f2(x,y,z)=c2. i believe i should be using gradients. thank you very much! === Subject: Re: Vedctor Calculus Question > Could someone help me to understand how to find the minimum distance > between a surface (say f1(x,y,z)=c1) and a line (f2(x,y,z)=c2. i > believe i should be using gradients. > thank you very much! A single equation, such as f2(x,y,z)=c2, can describe in a 3d space a surface, possibly a plane, but not a line. The vector parametric form for a line is g(t) = (u1 + u2*t, v1+v2*t,w1+w2*t), where (ui,v1,w1) is a point on the line and (u2,v2,w2) is a vector parallel to the line. If the surface and line intersect, i.e., the distance between the surface and the line is zero, then f1(u1+u2*t,v1+v2*t.w1+w2*t) = c1 is true for some real value of t. If the surface and line do not intersect and the surface has continuous gradients and no boundary curves, then the gradient of f2 at any extremal point (closest to or furthest from the line) must be perpendicular to (u2,v2,w2). === Subject: Re: Vedctor Calculus Question >A single equation, such as f2(x,y,z)=c2, can describe in a 3d space >a surface, possibly a plane, but not a line. I could *swear* that {(x,y,z) in R^3 : x^2+y^2=0} was a line, last time I looked. Lee Rudolph === Subject: Re: Vedctor Calculus Question >A single equation, such as f2(x,y,z)=c2, can describe in a 3d space >a surface, possibly a plane, but not a line. > I could *swear* that {(x,y,z) in R^3 : x^2+y^2=0} was a line, > last time I looked. > I stand correc, but it is not a very efficient way of doing lines, and certainly not the standard way. === Subject: Re: Vedctor Calculus Question >A single equation, such as f2(x,y,z)=c2, can describe in a 3d space >a surface, possibly a plane, but not a line. > I could *swear* that {(x,y,z) in R^3 : x^2+y^2=0} was a line, > last time I looked. > Note that z is unrestric. It might not hurt to look again. === Subject: Re: Vedctor Calculus Question >>A single equation, such as f2(x,y,z)=c2, can describe in a 3d space >>a surface, possibly a plane, but not a line. >> I could *swear* that {(x,y,z) in R^3 : x^2+y^2=0} was a line, >> last time I looked. >Note that z is unrestric. Oh, I do note that, I do, I do. >It might not hurt to look again. You go first! Lee Rudolph === Subject: Re: Vedctor Calculus Question >A single equation, such as f2(x,y,z)=c2, can describe in a 3d space >a surface, possibly a plane, but not a line. > I could *swear* that {(x,y,z) in R^3 : x^2+y^2=0} was a line, > last time I looked. > This actually happened. Many years ago a problem similar to this came up in a CalcIII class I was teaching. I mentioned that situations like this are called Degenerate case A girl raised her hand and said But that's what my Father says *I* am!! Bob Pease === Subject: Vigier V Conference Topics for Debate Comments by Jack Sarfatti on excerpts from: attention.) ABSTRACT Each approach to the quantum-gravity problem originates from expertise in one or another area Hi Jack, I can feel your intense interest to find the mechanism of gravity and objects but are instead wave structures in a quantum space. Our perception of their properties was 'schaumkommen' of the wave structures. (appearances.) I disagree. I agree with the deBroglie-Bohm-Vigier pilot theory that from information waves. IT FROM BIT matter cores /zpf < 0 that balance the centrifugal repulsion from quantized rotation about their centers of mass and from the repulsive self electric charge. the pilot wave information BIT landscape it is rolling on in a generalized gradient flow including the fiber space connections or gauge potentials as in the Bohm-Aharonov effect that is the Josephson effect in the macro-quantum case. That is action without reaction for the micro-quantum approximation with signal locality that applies to not apply to complex macro-quantum systems. Einstein agreed, but nobody worked it out. False. It's all worked out in Bohm and Hiley's The Undivided Universe. Now, it has been worked out. see QuantumMatter.com and SpaceandMotion.com The results are amazing. 1) All the natural laws are found as properties of the wave structure of the electron. 2) Everything grows out of only two principles which are properties of one thing - space. Awesome. Gravity is the simplest piece of cake. Take a look. I would love to have your thoughts. I do not know what you mean. Have you derived the equations for general relativity from the information wave? That is precisely what I have done for the giant vacuum pilot wave along with the unified dark energy/matter local field. Any new proposal must be couched in mathematical language and must in suitable limiting cases yield the battle tes equation of theoretical physics such as Guv = (8piG/c^4)Tuv Maxwell's equations etc. Otherwise it is not legitimate physics IMHO. Also there must be contact with experimental observations both in terms of prediction and explanation as nicely presen in David Deutsch's book The Fabric of Reality for example in the chapters on proper methodology in theoretical physics. Ditto for the excess verbal baggage of less by David C. Williams below on the nature of c in E = mc^2. The hard core of what is behind this can be found in the book by Wheeler and Taylor's introductory text on Einstein's relativity. The basic idea of geometrodynamics is the block universe of 4 dimensions with time and space mixing together in changes of perspective of uniformly moving observers in the globally flat case without gravity to begin with. The issue is the invariance of the 4D line element ds under the relevant groups of local frame transformations at a fixed spacetime event P. Given a local frame of reference with coordinates x,y,z, t ds^2 = dx^2 + dy^2 + dz^2 - c^2dt^2 = dx'^2 + dy'^2 + dz'^2 - c^2dt'^2 Here c must be invariant under the group as in the Lorentz transformations dx' = (1 - (v/c)^2)^-1/2[dx - vdt] dt' = (1 - (v/c)^2)^-1/2[t - vx/c^2] dy' = dy dz' = dz for a nonaccelerating frame shift at constant velocity v along the common direction x parallel to x' of the two global inertial frames S and S'. One cannot describe gravity this way if one insists on retarded causality of no teleological future causes of past effects associa with the ideas of destiny, fate and purpose. could use Newton's gravity with global special relativity to produce the three classic tests of GR provided one introduced the Wheeler-Feynman-Dirac-Hoyle-Narklikar trick of advanced potentials in addition to retarded potentials. The fact that Puthoff gets those tests as well with his variable dielectric vacuum model is no great achievement either because Einstein's classical geometrodynamics goes beyond those tests, e.g. gravimagnetism and gravity waves and black holes. With gravity one must use LOCALLY curved spacetime in which at spacetime point event P ds^2(P) = guv(P)dx^udx^v with summation convention u,v, = 0,1,2,3 There are two LOCAL symmetry groups here. The Poincare group is no good anymore. The translation subgroup symmetry of the Poincare group is broken by the locally variable Diff(4) curvature tensor that is the essence of gravity. The local Lorentz group of invariant tipped light cone structure is obeyed in the tangent fiber space attached to P. The base space of the tangent bundle obeys the Diff(4) group of LOCAL general coordinate tensor transformations xu' = x^u'(x^u) that replaces the translation subgroup of the globally flat Poincare group of special relativity. This is all for zero torsion of course. All LOCAL observables must be tensors or spinors under both groups. A spinor is a square root of a tensor. Einstein's equivalence principle is mathematically represen by the tetrad map eu^a(P) from locally flat tangent space inertial coordinates a to locally curved base space non-inertial coordinates u. The a -> a' transformation is via the 6-parameter Lorentz group of special relativity. The u -> u' transformation is via the 4-parameter Diff(4) group of general relativity. dx^u = eu^a(P)dx^a nab = ea^u(P)eb^v(P)guv(P) Local elimination of the non-tensor connection field for parallel transport of tensors along world line paths normally associa with Newtonian gravity acceleration g for example. These are g-forces or inertial forces from accelerating non-inertial frames like the surface of the rotating Earth for example. They are not inhomogeneous tidal variations in the g-force from the curvature tensor, which are never locally elimina although they are here on Earth very small of order (scale of measurement) 10^-13 in centimeters. Where nab is the flat space-time constant metric tensor of special relativity and guv(P) is the locally variable metric which represents a real gravity field only when the 4th rank curvature tensor of tidal forces does not vanish. You can have a variable guv(P) without a real gravity field from using a non-inertial local frame that is accelerating without tidal forces. This is not physically of great interest however. A LOCAL tensor that vanishes in one LOCAL frame vanishes in ALL LOCAL frames at fixed point event P for ALL relevant symmetry groups. If tuv = 0 then tab = 0 and vice versa. There is no such thing as a gravity force anymore in this non-Newtonian paradigm of geometrodynamics. Newton's gravity equations are regained in the limit of weak curvature and slow speeds compared to c. If there that minimize their dynamical action in the given metric field guv(P) Light rays move on null geodesics ds^2 = 0. The invariance of the speed of light c in global special relativity is replaced by the above remark! In general there are gravimagnetic cross terms in the case of nonstationary metrics and this complicates what is meant by the speed of light. For example, if there are no gravimagnetic cross terms in a simple case with spherical polar coordinates for a non-geodesic observer subject to spin 1 gauge forces like ds^2 = grr(P)dr^2 - gthetatheta(P)dtheta^2 + gphiphi(P)dphi^2 - c^2gtt(P)dt^2 For a light ray we have 0 = grr(P)dr^2 - gthetatheta(P)r^2dtheta^2 + gphiphi(P)(rsin(theta))^2dphi^2 - c^2gtt(P)dt^2 with the usual convention that the LOCAL metric field guv(P) is a pure dimensionless number and r(P) is the Schwarzschild curvature radial coordinate defined such that the surface area surrounding the center in the static spherically symmetric spacetime geometry has the Euclidean area 4pir(P)^2 . Consider the null radial geodesic, dtheta = dphi = 0 0 = grr(P)dr^2 - c^2gtt(P)dt^2 0 = dR^2 - c^2dT^2 where dR = grr(P)^1/2dr dT = gtt(P)^1/2dt dR and dT are physically measured space and time intervals for the light ray using meter sticks and clocks or radars by the non-geodesic observer for small separations between two lightlike separa events P and P'. Small means compared to the local radii of spacetime curvature. For example in the static spherically symmetric Schwarzschild vacuum metric solution of Ruv = 0 for r > 2Gm/c^2 gthetatheta = 1 gphiphi = 1 grr(P) = (1 - 2Gm/c^2r)^-1 gtt(P) = (1 - 2Gm/c^2r) The black hole event horizon is at gtt(P) = 0 dR = (1 - 2Gm/c^2r)^-1/2dr But the circumference C = 2pir The change in C for dr is dC = 2pidr Therefore dC/dR = 2pi(1 - 2Gm/c^2r)^1/2 --> 0 at the event horizon. The physical radius R = integral dR is much larger compared to physical circumference C as it would be in flat 3D space. If one keeps R fixed ~ h/mc ~ G*m/c^2, the micro-geon of Wheeler's Mass without mass Charge without charge Spin without spin shrinks to a point in high resolution Heisenberg microscope scattering probes with r ~ h/p for momentum transfer p like SLAC deep inelastic electron scattering off protons. This is a semi-classical theory without quantum electrodynamic vacuum polarization zero point energy density effects, however the latter were shown by Feynman and Schwinger to obey the Poincare group in the absence of gravity. The price for this is the obscure renormalization, which may not be internally mathematically consistent although its predictions are in remarkable agreement with experiments. Indeed, the requirement of renormalization with a finite number of fudge factors or epicycles :-) has been a very useful rule of thumb. Directly micro-quantizing Einstein's general relativity is not renormalizable, i.e. one needs an infinity of epicycle fudge factors. That tells us we have asked the wrong question. As John A. Wheeler says: The Question is: What is The Question? Resemblances of Wheeler's remark to Cantor's diagonal argument and Godel's incompleteness theorem of self-referential spontaneous self-organization are not accidental and random. Wheeler thinks of the universe as a self-exci circuit of observer-participators. The velocity of light c in ordinary non-gravitating vacuum with /zpf ~ 0 is directly measured by a variety of techniques. It is an observable measurable property. The velocity of light in a medium is c/n where n is the index of refraction. The physical vacuum also has an index of refraction n(vac) that is very close to 1 in most situations. This small variation comes primarily from vacuum polarization zero point fluctuations of the off mass shell or virtual electron-positron plasma electrically neutral ionized plasma inside the vacuum. This is vacuum. One must be careful in how to use both special and general relativity when polarization effects in real on mass shell media are considered. In the case of special relativity one should, for example, consult the text books by Arnold Sommerfeld, Panofsky and lips, Landau and Lifz. A real on mass shell medium in a sense spontaneously breaks translational symmetry on scales larger than the unit cell of the lattice as described in more detail by P. W. Anderson in his More is different series of papers collec in A Career in Theoretical Physics (World Scientific) When one includes all dynamical degrees of freedom including those inside the unit cell of the lattice, global special relativity is restored to the propagation of light in a real medium in the usual situation where gravity tidal forces are negligible. appropriate parties (bcc's to you and Toby) to stimulate wider discussion and understanding of the important points you have raised towards re-evaluation and correction of fundamental errors in scientific conceptualizations since the key departure of Newton's work neutering science by his using his mathematicalizations which did not incorporate properly his own determined religious faith in the absolute nature of truth as per his belief in God. I edi you posts lightly for clearer reading per common American English punctuation etc., and changed one word from proof to idea relating to the Theosophical science quote so that your point was not mistaken as that quote you ci being some kind of empirical experimental proof of the your choice of proof over idea please expand on this in your next post to correct my misunderstanding and I will forward appropriately with apologies. Your discussion properly considered, by those to whom it was sent, should also go a long way towards restoring, or integrating, ethics into the scientific discipline of thought since the only way out of present conundrums in science is to replace uncertainty about uncertainty with certainty about the absolute nature of truth itself and let the chips fall where they may in terms of how this change in principle modifies scientific perception of the nature of reality, the various theory equations etc. I noticed in your writeups that you reference C as the constant value of the speed of light in several places and then in one place you seem to reference it as the velocity of light. I understand that in his earlier works, especially in German, Einstein used the term velocity and then over years he too began routinely using speed apparently due to the mathematical convention dictating that by definition the value of the square of the direction component of the square of a vector property is defined identically equal to one. Thus, in trying to understand, for example, what is the true value of, say, (10mph-North)^2, the square of the velocity of ten miles per hour in a northerly direction, the simple (2+2=4) logic of ordinary math is thrown out the window by this mathematical convention per this dictum and the normal logical value of the square of this vector quantity (100m^2/h^2-North^2) is defined for all intents and purposes as equal to (100m^2/h^2), ie, like saying because we cannot mentally grasp or understand what it means (North)^2, we define it to be identical to one, ie, no meaning at all. While this may seem a trivial point for all purposes within the realm of considering physical systems dynamics from the point of view of current science since apparently Galileo's time, ie, the exclusively objective nature of reality, ie, that observer and observed are separate and all physical systems that are real exist independenttly of and identically observable by all observers, or they are not considered real by science when they are not reproducible by all observers at all times, in the case of C^2 as the proportionality constant between the value of the Energy of any given system of reality under observation and the value of the mass of that system, and since C itself appears in so many equations of electrodynamics etc., herein apparently lies another overlooked fundamental misconception of scientific thought compromising the absolute nature of truth since C itself is not pegged to the notion of an external objective reality reference frame but is pegged to the identity of the observer. That is to say, since C is non-additive and its square (C^2) is the proportionality constant between the values of energy and mass of real physical systems then this mathematical convention seems evidently the main limit of current mathematics to overcome for a full understanding of the relative nature of reality, ie, the relationship depic in Buddhism (and in Hinduism I believe) that each person's mind is the creator of the universe relative to the identity of that person, ie, the ego-centric nature of the universe. While this view seems rightly to folks like Dr. Sarfatti as psycho-babble it nevertheless is the view that offers a mathematical handle for a starting point to conceptualize and integrate into modern physical theories this precept that there is a consciousness factor at work between the nature of the observer and the nature of the system of reality under observation, ie, a relationship of mind between observer and observed as well acknowledged by quantum physics experiments over last decades where he describes this principle as observership. Many scientists are wrestling with this notion of the relationship of mind between observer and observed, eg, deno in O'Leary's books as the consciousness factor and in Dr. Sarfatti's post quantum physics of consciousness theory equations by their complexities that include the Uncertainty Principle mathematics and depict the operation of intent on the mental field of matter causing a 'back-action in time' reflecting back via that mental field of matter in a 'cybernetic feedback loop of consciousness' of predictible 'moment of consciousness' duration which corellates well with latest experimental results in neuroscience etc even though in Sarfatti's view, in my words, the observer is transparent ie, there is no accounting for variations between observer identities and corresponding variations in observable systems dynamics from observer to observed (non-reproducibility by all observers at all times of all physical systems dynamics, eg, psi-phenomena), ie, the differences in each observer's 'mind' impacting the physical systems dynamics of the 'reality' which each observer observes. Back-action is not temporal. It is the direct reaction if IT back on its BIT field. IT's BIT field quantum potential Q now has sources and is not fragile, but has macro-quantum phase rigidity of which Andrei Sakharov's metric elasticity is an example. IT is no longer a test from in spontaneous self-organization - the participatory universe as a self-exci circuit. It is not to be confused with the Wheeler-Feynman advanced potential from future to past. It is true that when the limits of micro-quantum theory without back-action hence with signal locality are transcended, then one gets presponse signal nonlocality which mimics an advanced potential effect. Back-action in my sense as quantum action + post-quantum reaction, and advanced potentials are, of course, not incompatible in my theory in which EPR micro-quantum nonlocality with signal locality are as in John Cramer's transactional generalization of the Wheeler-Feynman classical advanced potential as first no by Costa de Beauregard back in the 1970's. Antony Valentini shows that post-quantum back-action that pushes the system away from sub-quantal heat death causes signal nonlocality like what is seen by Dick Bierman in his mind-matter presponse experiments. Macro-quantum BEC systems in particular have post-quantum back-action IMHO. The above is my latest attempt to explain in words what I have rendered since 1974 into low level mathematical equations of a unified field theory (referencing field of awareness and the human mind's consciousness orientation function of light as correction factor to add back this omit true extra value of the square of the direction component of C^2 which is more than (north)^2 because of this fact that C is non-additive and therefore as such is fundamental, being the only physical not 'pegged' to the notion of the exclusively objective nature of reality but rather 'pegged' to the conceptualization of the 'relative' (or 'ego-centric') nature of reality a conceptualization which is obvious in human daily life via common sense in all other realms and is throughout the history of human thought a fundamental principle as discussed in new age psycho-babble in such terms as we are the center of our own universe and by application of the human mind we can influence and change the nature of our universe. The above paragraph by David Williams is New Age cargo cult pseudoscience IMHO on a par with crystal power, orgone, spiral dynamics, monoatomic highly deformed nuclei superconducting Ormus powder et-al. It is not even wrong in Wolfgang Pauli's sense. Bruce DePalma is the only person who has looked at the four equations of my Tetron Natural Unified Field Theory and the minimal discussion of their meaning presen to him soon after I met him in May 1979, and his reaction in subsequent soon talk with me was, David, you know, I understand your theory. 'Seeing is believing, right?' was his response with a glimmer of humor behind his eyes that made me know that he had hit the nail on the head with this response which zero's in on the paradoxical relationship of mind between seeing and believing as it relates to all levels of human thought including science, religion, spirituality, politics, etc. The above paragraph by David Williams is New Age cargo cult pseudoscience IMHO on a par with crystal power, orgone, spiral dynamics, monoatomic highly deformed nuclei superconducting Ormus powder et-al. It is not even wrong in Wolfgang Pauli's sense. Exclusive of Dr. Sarfatti's vigorous ... criticisms, everyone else since has either said so what? in response, or like O'Leary have just ignored and refused to respond to this theory of mind, with the single exception of Dr. Fred Wood who listened to my first-ever public lecture on my theory, on September 10, 2001, at my alma mater California State University at Northridge, and after made a point of telling me that he would think seriously about what I had said (a prepared written formal read aloud lecture archived at http://groups.yahoo.com/group/gcsc-csun/message/6 ) Subsequently, I emailed Dr. Wood and sugges that the next step in the application of my tetron thesis is beyond the mathematics of my education as a Bachelor of Science in Chemistry, ie, how to understand the (tensor?) mathematical relationship between this correction factor Tetron -- the mathematical function applied to the square of the speed of light to correct it to its true value of the square of the velocity of light orien relative to the identity of the observer, ie, adding back the square of the vector component of C to overcome above described mathematical convention, ie, compromise about the nature of light and the absolute nature of truth itself in all places where C^2 appears in physics equations -- as Tetron applies to C^2, and since many equations particularly in electromagnetism contain C, there must be a similar correction factor to apply in such equations which is also the missing link in understanding the consciousness factor as it relates to these new space energy technologies and the expec reconciliation of their presently conflicting theories of operation. The above paragraph by David Williams is New Age cargo cult pseudoscience IMHO on a par with crystal power, orgone, spiral dynamics, monoatomic highly deformed nuclei superconducting Ormus powder et-al. It is not even wrong in Wolfgang Pauli's sense. Since your theoretical approach well includes deep background understanding on this Eastern osophy concept of the mind as the creator of the universe per Vedic knowledge you write and feedback on my above views will help stimulate productive thinking towards a deeper understanding of this consciousness factor as it also needs to be formalized in order to correct the mind of science and fully understand what is going on with all these various new space energy technology experiments and the theories posi to try and understand these results as well as how some of the theories (like yours and Joseph Newman's) have predic and perhaps even empowered the successful experimental results that you have each obtained by different configurations of rotating magnetic systems with entirely different theoretical underpinnings yet with similar overunity results. Consciousness IMHO is when one has post-quantum back-action which excites the MACRO-QUANTUM BIT BEC field into self-awareness. Our minds are macroscopic non-classical information fields of both active and inactive information in the Bohm-Hiley sense. Flashes of memory are the activation of unoccupied basins of attraction of the MACRO-QUANTUM BIT LANDSCAPE when the IT system point of sub-microtubular hydrophobically caged electric dipole Frohlich collective modes roll into that basin. In the torsion field theory developed in recent decades from the Russian language-mind views expressed in mathematical language and with deeper consideration of many documen psi-phenomena experiments in former Soviet Union, going back to the 1950's-60's apparently, there may also be this idea of a relationship of mind between observer and observed but the details of how this is represen in this theory are unclear to me at my level of math education and literature availability. But it is clear from my personal conversation with Dr. Shipov courtesy of Dr. Sarfatti's kind invitation for my informal participation with his group in San Francisco one day a few years ago, that torsion field theory also is perplexed by the results of DePalma showing variation in gravitational behavior between spinning and non-spinning ball bearing drop results discussed in earlier post. I do not believe DePalma's claims. Gennady's beliefs in psi are not directly connec with his torsion math. Bill Page talked about the latter at Vigier IV. Creon Levit investiga such claims at ISSO 1999-2000 that Williams refers to here. Creon was not impressed with any of the New Age Free Energy claims promo by David. But Creon can speak for himself. My hunch here on this is that rotating objects too have a vector property which analogous to C discussed above, is being overlooked in its importance as it relates to the observer because every rotating system also may, similar to C, be seen in the view of its orientation and rotational properties as relates to the relative identity of the observer. I think that this other application of what I talk about above will not come here until this issue about C is resolved, but that there is an important connection between the correc true value of C^2 as per above and a deeper understanding and correction also with torsion field theory, although the math involved is way beyond my education level to deal with as a language to express the principles I have tried my best above to explain in my style of California Chemical English The above paragraph by David Williams is New Age cargo cult pseudoscience IMHO on a par with crystal power, orgone, spiral dynamics, monoatomic highly deformed nuclei superconducting Ormus powder et-al. It is not even wrong in Wolfgang Pauli's sense. David Crockett Williams 661-822-3309 Chartered Life Underwriter Bachelor Science Chemistry www.angelfire.com/on/GEAR2000/vision.html http://groups.yahoo.com/group/drums-of-peace http://groups.yahoo.com/group/new-energy-solutions http://www.josephnewman.com Red Silk Road Peace March Project USA, California, Japan, Korea, China, Nepal, India, Pakistan, Afghanistan, Iran, Iraq, Jerusalem, http://groups.yahoo.com/group/silk-road-to-peace http://groups.yahoo.com/group/dharma-walks One Person Can Make a Difference www.kucinich.us Rep. Kucinich http://groups.yahoo.com/group/Kucinich-for-President Spiritualism, The Highest Form of Politics For a Culture of Peace & Community Our Spiritual Unity Re-Awakening www.leonardpeltier.org www.horseforgovernor.com www.prophecykeepers.com http://web.mahatma.org.in www.peaceinspace.com www.cesarechavez.org www.brianwillson.com www.dharmawalk.org www.sathyasai.org www.tewari.org www.prop1.org === Subject: Re: Is this newsgroup useless? > Moderating this group is not an option. The USENET Powers that Be > (otherwise knows as the moderators of news.announce.newgroups) have > decreed that proposals for changing the moderation status of existing > groups will be not be accep. If you want a modera version of > sci.math then you'll have to propose a new newsgroup. But doesn't sci.math.research exist? And isn't it modera? So what is all the fuss about? Joachim -- Trau niemals einem Stollentroll! === Subject: Re: Is this newsgroup useless? > But doesn't sci.math.research exist? And isn't it modera? So what is > all the fuss about? sci.math.research doesn't allow discussions of elementary topics (homework problems), and other math rela things like Latex, whether Maple is better than Mathematica, how easy it is to lose a job by going to the Joint Meetings, whether electronic journals are as good as paper ones, and so on. Bart === Subject: Re: Is this newsgroup useless? > But doesn't sci.math.research exist? And isn't it modera? So what is > all the fuss about? sci.math.research is orien towards mathematical research at a fairly high level. sci.math isn't (although such topics arise here); it's scope is much broader. === Subject: Re: Is this newsgroup useless? > The real > problem is that this is an *unmodera* newsgroup. All posters are > permit. > I have two other main newsgroup interests. One of them is > christianity. In that case, I avoid the unmodera groups > at like a Pharisee avoids a leper. They make sci.math look like > a candle next to the space shuttle taking off. It takes a hardworking, > patient and wise moderator to keeps christians behaving like...uh.. > christians. So in that sense, your half right. > But my other interest is homebrewing, What's your favorite style? I like to brew IPA's. But, so far, my best brew is a lagered Bohemian Pilsner. Smooooth. I'm having a little problem with mashing ... poor yield. Math + Homebrew = FUN. > and that group is UNmodera, > but the most pleasant and helpful and unflaming group on all of USENET. > Every newbie who comes along asking the same dumb question that's > been asked 17 trillion times is welcomed with open arms, given > kind advice and we cheer that another lost sheep has been conver > from the evils of Budmilloors and demon megaswill. So your half > wrong. > Half the problem here is that it's unmodera. The other half is > that it's popula by overly-anal-retentive jerks who think it's > going to be important to point out that I spelled you're your > twice in the preceding paragraphs. > There's something the same about fanatic legalists in the religious > groups and anal mathematicians, in that they think they've scored > something if they catch you in an error. AHA! You've typed > slander when you should have typed libel! So what? Therefore > I'm an idiot and he's a savant and now I have to erase his > chalkboards for him? Hardly. I'm going to have a homebrew and > hang out with the cute chicks while he re-catalogues his PowerRanger > Collector's Cards. > I _thought_ we had beaten these guys up sufficiently in the high > school locker room that they'd be quiet by now. All I did was > explain that if we'd all place our duffel bags perpendicularly > on the benches, there would be room for all of us to get dressed > at once. I really don't think that was sufficient reason for > them to put Nair in my bottle of Prell. > Maybe the real problem is that a guy can't e-mail a matburn. > Bart === Subject: Re: Is this newsgroup useless? >> But my other interest is homebrewing, > What's your favorite style? I like to brew IPA's. But, so far, my best > brew is a lagered Bohemian Pilsner. Smooooth. I'm having a little > problem with mashing ... poor yield. Math + Homebrew = FUN. I probably to an IPA every other batch, because they're ready early and I seem to run out of beer so fast. I often make the Sister Star variety because I like heavily hopped versions. But my favorites are double bocks, even though they have to age forever. The thing that increased my mash efficiency the most was doing a mash-out. (In a 10-gallon batch) just before sparging I drain off 3 gallons of wort, bring to almost boil, and then add it back to the mash. This brings the temp up into the 165 range and the sparging rinses out much more fermentables. (But you gotta' be careful not to go higher than 170.) But maybe you do that already. The other thing that helped me a lot was paying attention to pH and adding the right amount of calcium carbonate to the mash water. Gotta keep those enzymes happy. rec.crafts.brewing is a great group. I've nicknamed my liver Kenny, by the way... Bart === Subject: Re: Is this newsgroup useless? at 02:32 PM, No One said: > I guess that the time has come for me to ditch this group >altogether. It seems to have been taken over by deranged individuals >exposing their misguided ideas over and over again (Mr. Harris being >the best representative of this increasingly vocal group,) impervious >to any kind of logic reasoning; by people trying to get the group to >do their homework for them, and by plain idiots who post the most >irrelevant babbling (like this moron who posts numerological stuff, >while changing his profile frequently.) Kooks are endemic to Usenet. Your filter is your friend. Actually, sci.math is in good shape compared to some, even in the sci.* hierarchy. -- Shmuel (Seymour J.) Metz, SysProg and JOAT Unsolici bulk E-mail will be subject to legal action. I reserve the right to publicly post or ridicule any abusive E-mail. Reply to domain Patriot dot net user shmuel+news to contact me. Do === Subject: Re: Is this newsgroup useless? >> The O.P. may well be a troll. > Believe me, I am not. I am just expressing despondency about the status > quo nowadays. I have been reading sci.math, on and off, for some 14 years > now, and it has gotten steadily worse. With all the trolls, morons, > lunatics and otherwise deranged contributors to this group so prevalent > today, going through new headers every day has become a painful exercise. Why? Do you talk to the nntp-server via the raw protocol? Just use a decent news-reader and ignore certain Subject-lines and authors. Marc === Subject: Re: Is this newsgroup useless? > Just use a decent news-reader and ignore certain Subject-lines and > authors. He does use a decent newsreader, and he could ignore certain Subject-lines and authors with it. Joachim -- Trau niemals einem Stollentroll! === Subject: Re: Is this newsgroup useless? >> I'd certainly read sci.math.modera but who would moderate it? >> It would be a lot of hard work. >It wouldn't be so hard to read a message and decide whether to >post it. And having decided not to post it, to return the message >to the author with the (first) offending sentence highligh and >a pointer to the website with the posting guidelines. >The REAL hard work would be in the fielding of the the challenges >to the moderator's decisions. If the moderator was strict and did >his work well, the posting-decisions work would be minor (but a >daily chore, no doubt) since posters would quickly learn what was >acceptable and abide by the rules. The moderator, by being consistant >and fair, could keep his own work minimal. >It's when some dingbat engages him in an argument about whether >his post should have gone through and starts whining about free >speech and starts posting libelous crap about the moderator and >his fascist policies on sci.math and (as in one case I know) actually >takes the moderator to court, that things get out of hand. (The >idiot was laughed out of court, of course, but what a pain for the >moderator.) One buffoon on the christianity group got mad at the ads >with active embedded scripts, which, upon opening, of course, To bring the thread back on-topic, this reminds me of a mathematical problem recently raised by a member of my department, who shall remain anonymous. Suppose you (applies to male readers only!) had taken advantage of every offer of the above type received, and all had worked as claimed. Estimate how long it would be. Derek Holt. === Subject: Re: Is this newsgroup useless? >>[...] One buffoon on the christianity group got mad at the ads >>with active embedded scripts, which, upon opening, of course, >To bring the thread back on-topic, this reminds me of a mathematical >problem recently raised by a member of my department, who shall remain >anonymous. Suppose you (applies to male readers only!) had taken advantage >of every offer of the above type received, and all had worked as claimed. You're assuming we haven't, and that if we had they wouldn't work. >Estimate how long it would be. One learns not to step on anything pretty quickly... >Derek Holt. ************************ === Subject: Re: Is this newsgroup useless? > The number of replies is the thread's rating. Apparently, post's quality has > nothing to do with the rating. Now, face it: the JSH show has the highest > rating in sci.math. > That's what makes it so sad - that the rantings of that pathetic loony > seem to be stuff that so many contributors to sci.math are so interes > in. I'm puzzled why this bothers you so much. The huge majority of posts on sci.math are about mathematics. It's easy to skip the other threads, assuming a moderately decent newsreader. === Subject: Re: Is this newsgroup useless? >> The number of replies is the thread's rating. Apparently, post's quality has >> nothing to do with the rating. Now, face it: the JSH show has the highest >> rating in sci.math. >> That's what makes it so sad - that the rantings of that pathetic loony >> seem to be stuff that so many contributors to sci.math are so interes >> in. >I'm puzzled why this bothers you so much. The huge majority of posts on >sci.math are about mathematics. I'm glad you said that, because I wan to but hesita to do so because after all I'm one of the guys who's part of the problem according to various posts here. Seems to me that an even huger majority of the _threads_ are about mathematics, making it even easier to filter out the crap if you want. >It's easy to skip the other threads, >assuming a moderately decent newsreader. ************************ === Subject: Re: Is this newsgroup useless? > The number of replies is the thread's rating. Apparently, post's quality has >> nothing to do with the rating. Now, face it: the JSH show has the highest >> rating in sci.math. That's what makes it so sad - that the rantings of that pathetic loony >> seem to be stuff that so many contributors to sci.math are so interes >> in. I'm puzzled why this bothers you so much. The huge majority of posts on >sci.math are about mathematics. > I'm glad you said that, because I wan to but hesita to do so > because after all I'm one of the guys who's part of the problem > according to various posts here. Why not tell it like it is, Ullrich? You're the epitome of a mathie sadist! --John > Seems to me that an even huger majority of the _threads_ are > about mathematics, making it even easier to filter out the crap > if you want. >It's easy to skip the other threads, >assuming a moderately decent newsreader. > ************************ > === Subject: Re: Is this newsgroup useless? >>I'm puzzled why this bothers you so much. The huge majority of posts >>on sci.math are about mathematics. > I'm glad you said that, because I wan to but hesita to do so > because after all I'm one of the guys who's part of the problem > according to various posts here. Well, as I think about it more, the social aspect of the newsgroup is part of its appeal also. My original outline for the strict moderation would leave the atmosphere pretty antiseptic, after all. We have to feel like we're sitting around the math lounge chatting and if we want to go off on tangents then we can if we feel like it. As someone said, a modera group was tried before, and almost no one participa. Nice argument Are you going to Phoenix this year? I never go to those silly things. Waste of time. Waste of time! I'm giving a short course! So you're one of those idiots padding his vita by pretending to be an expert on a non-topic? What a bozo! 'Bozo'? I hope that clown sues you for copyright infringement! It's not 'copyright' it's 'trademark', Krusty....... After all, most of us are nerds, and this may be our only social life....;-) So perhaps the _real_ problem is that the math lounge has 2000 people in it, and the cross conversation requires a bit more subtle etiquette than a normal math lounge with only 5 or 10 people. Several people have commen that the filtering systems should work fine. Sure they do, if you continuously update them. Maybe some semi-official header guidelines (that is some sort of netiquette for sci.math) that aids in efficient filtering would be the thing to persue. Violators could be politely informed of the conventions, and if they choose to ignore them, then there's nothing we can do about it, except ignore them, but that should be sufficient. I guess having JSH in certain headers was a step in that direction, but I don't really have any good ideas as to what header guidelines should be. I'm just thinking outloud. Bart === Subject: Re: Is this newsgroup useless? >[...] >Several people have commen that the filtering systems should >work fine. Sure they do, if you continuously update them. If you continuously update them, right. That's really a _lot_ of work with a decent newsreader. Like take Agent, for example. I download the new headers. Years ago I'd just sit there for a few minutes with a finger on the N key, moving to the next new post and hitting Enter if I wan to read it. These days I sit there with one finger on the N key and one on the I key - when a wacky thread appears (in some other group where I don't want to see the wacky threads, not here) I hit the I key instead of the N key, and I'm never bothered by that thread again. Which is to say that simultaneously scanning for things you want to read and killfiling things you don't want to read in the future is _no_ harder than just browsing through the headers, if you're using a decent newsreader. You must have internet access - Agent has a free version, so I don't see what the problem is. Well, you do need to be able to find the N key and the I key. That can be tricky at first, but you only have to do it once per session; just leave your fingers there. >Maybe some semi-official header guidelines (that is some sort >of netiquette for sci.math) that aids in efficient filtering >would be the thing to persue. Violators could be politely informed >of the conventions, and if they choose to ignore them, then there's >nothing we can do about it, except ignore them, but that should be >sufficient. >I guess having JSH in certain headers was a step in that direction, >but I don't really have any good ideas as to what header guidelines >should be. I'm just thinking outloud. You're certainly doing _something_ out loud - hard to say whether thinking is the right word, since the problems you're complaining about are so easy to fix. Luckily this is not a modera group, so you're free to bounce ideas off us just like JSH is... >Bart ************************ === Subject: Re: Is this newsgroup useless? >so I don't see what the problem is. >Well, you do need to be able to find the N key and the >I key. That can be tricky at first, but you only have to >do it once per session; just leave your fingers there. Actually that could be a hard task, to locate those two keys. R'ght 'ow, for ''sta'ce, ' ca''t seem to do 't. dave (short for dav'd rus'') === Subject: Re: Is this newsgroup useless? > You're certainly doing _something_ out loud - hard to say whether > thinking is the right word, since the problems you're complaining > about are so easy to fix. Luckily this is not a modera group, > so you're free to bounce ideas off us just like JSH is... I haven't been complaining at all. Just chatting with the original complainer. Everyone knows what the really, really, absolutely true problem is, however, and it is the insufferable rudeness of several posters. But like you say, these things are easy to fix. === Subject: Re: Is this newsgroup useless? >[...] >Several people have commen that the filtering systems should >work fine. Sure they do, if you continuously update them. >> You're certainly doing _something_ out loud - hard to say whether >> thinking is the right word, since the problems you're complaining >> about are so easy to fix. Luckily this is not a modera group, >> so you're free to bounce ideas off us just like JSH is... >I haven't been complaining at all. Just chatting with the >original complainer. Everyone knows what the really, really, >absolutely true problem is, however, and it is the insufferable >rudeness of several posters. But like you say, these things >are easy to fix. > See, that wasn't all that hard. ************************ === Subject: Re: Is this newsgroup useless? >So perhaps the _real_ problem is that the math lounge has >2000 people in it, and the cross conversation requires a bit >more subtle etiquette than a normal math lounge with only 5 or >10 people. Nah. The _real_ problem is that the math lounge has 2000 people in it, of whom a number (probably not out of proportion to that in the general population) have the bad qualities of mind that made life hell for John Nash and those around him, without having the good qualities of mind that made Nash a mathematician of note. That is: it's not the nerds, it's the nuts. Lee Rudolph === Subject: hw help -- continuity Folks, I have a couple questions. This is homework, so please post a nudge, not a solution. 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) After drawing some graphs, this seems pretty obvious for the single point a0 -- max(f,g) has 2 cases: it equals to f or g. Either is continuous. However, this question implies continuous on R, not just at a single point. Any ideas how to approach this? 2)Let f be a function with the property that every point of discontinuity (ie the lim (x->a) f(x) exists, but is not equal to f(x)) is a removeable discontinuity. This implies lim (y->x)f(y) exists for all x, but f may be discontinuous at some (even infinitely many) numbers x. Define g(x) = lim (y->x) f(x). Prove g is continuous. --I don't even know where to start with this one. -earl- === Subject: Re: hw help -- continuity > Folks, > I have a couple questions. This is homework, so please post a nudge, > not a solution. > 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) > After drawing some graphs, this seems pretty obvious for the single > point a0 -- max(f,g) has 2 cases: it equals to f or g. Either is > continuous. However, this question implies continuous on R, not just > at a single point. Any ideas how to approach this? I'm confused. If you can show that max(f,g) is continuous at each point, then you have shown that max(f,g) is continuous. However, you still have to prove that max(f,g) is continuous at a point given that f and g are both continutous at that point. Remember, the ideal of continuity is that one is making a statement about how control over the independent variable allows control over the dependent variable. For example, if h(t) represen the height of a balloon (h) as a function of time (t), then to say that h is continous is to say that if at a given time t0, if I confine my attention to times sufficiently close to t0, then the height of the ballon is guaranteed to be sufficiently close to h(t0). Formally, the two occurances of sufficiently are replaced by delta and epsilon, respectively. Thus, if I want h is a continutous function of t, suppose I want a guarantee that the balloon will now have change height by more than 1000ft. You might respond that this will be true if I confine my attention to a time period of 60seconds. So you have told me that if |t-t0|<60, then |h(t)-h(t0)|<1000. Suppose I want better--I want a guarantee that the balloon has not changed altitude by more than 100 ft. Well, you might tell me that now I must confine my attention to 20 seconds. You have told me that if |t-t0|<20, then |h(t)-h(t0)| < 100. Now, the above is the basic idea of continuity. In the first case, I demanded what to do of an epsilon=1000, and you told me that a delta=60 would suffice. Then I asked what I would need to get a guarantee for epsilon=100, and you told me delta=20. Note, but the way, that if delta=20 works for epsilon=100, then delta=10 also works for epsilon=100. That is, for each epsilon you have to produce a delta small enough so that changes in the independent variable of less than delta result in a change of less than epsilon in the dependent variable. For checking continuity, one need not provide an optimal or largest delta--this is part of the abstraction. Of course, if you told me that for epsilon=100ft I would need a delta of 0.0000000001sec, then this might not be useful for practical purposes; a continuous function can still jump around a lot. But for the abstract idea of continuity, you must merely argue that for at an arbitrary point, for a given epsilon>0, there exists a delta (perhaps a very small delta, of no real use) such that a change in the independent variable of less than delta results in a change of the dependent variable that is *logically guaranteed* to be less than epsilon. Now back to the problem at at. We want to guarantee that max(f,g) doesn't change too quickly. We know that f and g don't change too quikly, so this is looking reasonable. Now we follow our nose and try the standard openning Let a0 be a point, and epsilon>0. [Ok, what now. Well we know that f and g are continuous. Let's write down what that means] So, for the particular epsilon lis about, there exists delta_1 such that |x-a0| 2)Let f be a function with the property that every point of > discontinuity (ie the lim (x->a) f(x) exists, but is not equal to > f(x)) is a removeable discontinuity. This implies lim (y->x)f(y) > exists for all x, but f may be discontinuous at some (even infinitely > many) numbers x. > Define g(x) = lim (y->x) f(x). Prove g is continuous. Try the one above again--if you still have problems, write back. -MIke > --I don't even know where to start with this one. > -earl- === Subject: Re: hw help -- continuity === Subject: hw help -- continuity >1)prove that if f,g continuous, then so are max(f,g) and min(f,g) >After drawing some graphs, this seems pretty obvious for the single >point a0 -- max(f,g) has 2 cases: it equals to f or g. Either is >continuous. However, this question implies continuous on R, not >just at a single point. Any ideas how to approach this? Show min(x,y), max(x,y), RxR -> R are continuous. Then as f,g are continuous, so are compositions min(f,g), max(f,g) ---- === Subject: Re: hw help -- continuity > 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) > After drawing some graphs, this seems pretty obvious for the single > point a0 -- max(f,g) has 2 cases: it equals to f or g. Either is > continuous. However, this question implies continuous on R, not just > at a single point. Any ideas how to approach this? There is a slight complexity. The point may lie on both f and g. You should try working directly from the definition for continuity and playing around with the inequalities associa with the min and max functions. === Subject: Re: hw help -- continuity > Folks, > I have a couple questions. This is homework, so please post a nudge, > not a solution. > 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) > After drawing some graphs, this seems pretty obvious for the single > point a0 -- max(f,g) has 2 cases: it equals to f or g. Either is > continuous. However, this question implies continuous on R, not just > at a single point. Any ideas how to approach this? Proving a function continuous at any point proves it continuous at every point. > 2)Let f be a function with the property that every point of > discontinuity (ie the lim (x->a) f(x) exists, but is not equal to > f(x)) is a removeable discontinuity. This implies lim (y->x)f(y) > exists for all x, but f may be discontinuous at some (even infinitely > many) numbers x. > Define g(x) = lim (y->x) f(x). Prove g is continuous. > --I don't even know where to start with this one. Does you definition of g(x) actually read g(x) = lim (y->x) f(x) or should it be g(x) = lim (y->x) f(y)? In the first case, g(x) = f(x) at all x, so is not continuous at discontinuities of f. In the latter case, does g(x) = lim (y -> x) g(y), for all x? === Subject: Re: hw help -- continuity === Subject: Re: hw help -- continuity >> 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) >> Any ideas how to approach this? >Proving a function continuous at any point >proves it continuous at every point. f(x) = 0 when x <= 0 = 1 when 0 < x is continuous at 1. Thus it's continuous at 0? ---- === Subject: Re: hw help -- continuity === > Subject: Re: hw help -- continuity >> 1)prove that if f,g continuous, then so are max(f,g) and min(f,g) >> Any ideas how to approach this? >Proving a function continuous at any point >proves it continuous at every point. > f(x) = 0 when x <= 0 > = 1 when 0 < x > is continuous at 1. Thus it's continuous at 0? But 1 is not any point, it is a specific point. To restate less ambiguously: If you prove f continuous at an arbitrary point, then it is continuous at every point And to prove it at an arbitrary point, you only need show that for an arbitrary x, g(x) = lim_{y -> x} g(y) === Subject: Re: After Coxeter > At one point or another I read parts of these books: > * Manfredo P. do Carmo: Riemannian Geometry > a very nice reading. good exercises > * R.W. Sharpe : Differential Geometry. Cartan's Generalization of > Klein's Erlangen Program. > very broad minded. not allways accurate. > * Kobayashi and Numizu > enciclopedic. > * J. Jost > the analytic view. very dense. > * Spivak's pentalogy > surpsingly, some parts of it are actually nice. Yes, now it's manufactured as a proper book, I'm saving up my pennies to buy it. > HTH > D.L. -- G.C. === Subject: Exponentative closure Can the reals be defined using repea exponentative closure? By the exponentative closure F, I define F/x as the set of all the zeroes of all the polynomial functions with coeffeicients AND exponents in F. For example, the the algebraics are the exponentative closure of the integers. Thus, it can be written A=Z/x. Does C=A/x? If not what does A/x equal? Can C be genera by repealy exponentatively closing the integers a finite number of times? If so, how many? A countable number of times? An uncountable number of times? === Subject: Re: Exponentative closure >Can the reals be defined using repea exponentative closure? >By the exponentative closure F, I define F/x as the set of all the >zeroes of all the polynomial functions with coeffeicients AND >exponents in F. For example, the the algebraics are the exponentative >closure of the integers. Thus, it can be written A=Z/x. Does >C=A/x? If not what does A/x equal? Can C be genera by >repealy exponentatively closing the integers a finite number of >times? If so, how many? A countable number of times? An uncountable >number of times? The set of all that is obtained is countable. This is because each polynomial has only a finite number of coefficients and exponents, and returns only a finite number of results. This is assuming that a clear definition exists of x^y if x is negative and takes the value |x|^y; more can be done. Doing this more than omega (the order type of the integers) times yields nothing new, because there are only a finite number of arguments for each extension. -- This address is for information only. I do not claim that these views are those of the Statistics Department or of Purdue University. Herman Rubin, Department of Statistics, Purdue University hrubin@stat.purdue.edu Phone: (765)494-6054 FAX: (765)494-0558 === Subject: Re: Exponentative closure >Can the reals be defined using repea exponentative closure? >By the exponentative closure F, I define F/x as the set of all the >zeroes of all the polynomial functions with coeffeicients AND >exponents in F. For example, the the algebraics are the exponentative >closure of the integers. Thus, it can be written A=Z/x. Does >C=A/x? If not what does A/x equal? Can C be genera by >repealy exponentatively closing the integers a finite number of >times? If so, how many? A countable number of times? An uncountable >number of times? Unless I misunderstand you, F/x is countable if F is countable. So no, a finite or even a countable number of exponentative closures won't do it: the union of countably many countable sets is countable. I don't know about an uncountable number of times. Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: Re: Exponentative closure >Can the reals be defined using repea exponentative closure? >By the exponentative closure F, I define F/x as the set of all the >zeroes of all the polynomial functions with coeffeicients AND >exponents in F. For example, the the algebraics are the exponentative >closure of the integers. Thus, it can be written A=Z/x. Does >C=A/x? If not what does A/x equal? Can C be genera by >repealy exponentatively closing the integers a finite number of >times? If so, how many? A countable number of times? An uncountable >number of times? > Unless I misunderstand you, F/x is countable if F is countable. So no, > a finite or even a countable number of exponentative closures won't > do it: the union of countably many countable sets is countable. I don't > know about an uncountable number of times. > Robert Israel israel@math.ubc.ca > Department of Mathematics http://www.math.ubc.ca/~israel > University of British Columbia > Vancouver, BC, Canada V6T 1Z2 A further question along those lines is what is is the set, E, of numbers genera by repea sums of products of rational powers of rationals? It is a subset of the algebraics, but does it form a field? What can be said about the set of sums and products of elements of E to the power of elements of E? === Subject: Re: Exponentative closure >A further question along those lines is what is is the set, E, of >numbers genera by repea sums of products of rational powers of >rationals? It is a subset of the algebraics, but does it form a >field? I believe so: if x_1 is a member of E, then so are its conjugates x_2, x_3, ..., x_n. Note that x_1 x_2 ... x_n is rational (being the constant term of a monic polynomial over the rationals whose roots are x_1, x_2, ..., x_n). And then 1/x_1 = x_2 ... x_n / (x_1 x_2 ... x_n) is in E. Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: Re: Exponentative closure >A further question along those lines is what is is the set, E, of >numbers genera by repea sums of products of rational powers of >rationals? It is a subset of the algebraics, but does it form a >field? > I believe so: if x_1 is a member of E, then so are its conjugates x_2, > x_3, ..., x_n. > Note that x_1 x_2 ... x_n is rational (being the constant term of a > monic polynomial over the rationals whose roots are x_1, x_2, ..., x_n). > And then 1/x_1 = x_2 ... x_n / (x_1 x_2 ... x_n) is in E. > Robert Israel israel@math.ubc.ca > Department of Mathematics http://www.math.ubc.ca/~israel > University of British Columbia > Vancouver, BC, Canada V6T 1Z2 If we say that a set, P, is exponentially closed if for all p,q in P, p^q is P, then can the complex numbers be defined as the field that is exponentially closed? Or even more simply, the set that is exponentially closed and contains -2 and 0? If not, what are the properties of the smallest field, S, that is exponentially closed (cardinality, algebraic completeness, convergence of Cauchy-Sequences)? Note: that I am only considering fields with characteristic 0. === Subject: Re: Exponentative closure Visiting Assistant Professor at the University of Montana. >>A further question along those lines is what is is the set, E, of >>numbers genera by repea sums of products of rational powers of >>rationals? It is a subset of the algebraics, but does it form a >>field? >> I believe so: if x_1 is a member of E, then so are its conjugates x_2, >> x_3, ..., x_n. >> Note that x_1 x_2 ... x_n is rational (being the constant term of a >> monic polynomial over the rationals whose roots are x_1, x_2, ..., x_n). >> And then 1/x_1 = x_2 ... x_n / (x_1 x_2 ... x_n) is in E. >> Robert Israel israel@math.ubc.ca >> Department of Mathematics http://www.math.ubc.ca/~israel >> University of British Columbia >> Vancouver, BC, Canada V6T 1Z2 >If we say that a set, P, is exponentially closed if for all p,q in P, >p^q is P, then can the complex numbers be defined as the field that is >exponentially closed? Or even more simply, the set that is >exponentially closed and contains -2 and 0? >Note: that I am only considering fields with characteristic 0. No; either set is too small. I assume that your operation ^:PxP -> P is just a partial operation, not defined at (0,0); so just redefine it to give ^(0,0) = 0. The smallest field of characteristic zero that is exponentially closed would be the closure of Q under the operation ^. Since ^ is a finitary operation (takes only a finite number of arguments), the closure of Q is obtained as follows: S_0 = Q; T_{n} = S_n cup ^(S_n,S_n) where ^(S_n,S_n) is the image of (S_n,S_n) in C; that is, all numbers of the form p^q with p,q in S_n, under that definition; S_{n+1} = T_{n} cup +(T_{n},T_{n}) cup -(T_n) cup *(T_n,T_n) cup ^{-1}(T_n-{0}) where +(T_{n},T_{n}) is the sum of any two elements of T_n, -(T_n) is the additive inverse of any element of T_n, *(T_n,T_n) is the product of any two elements of T_n, and ^{-1}(T_n-{0}) is the multiplicative inverse of any nonzero element of T_n Then the closure of Q is S_{omega} = Union_{nIf not, what are the >properties of the smallest field, S, that is exponentially closed >(cardinality, algebraic completeness, convergence of >Cauchy-Sequences)? So S=S_{omega}. Cardinality is clearly countable, by the argument above (a standard argument of General Algebra). You would not get convergence of Cauchy sequences: since this is countable, there is a real number which is not in the set, and of course that real number is the limit of a cauchy sequence of rationals, which are all in S. I suspect algebraic completeness will also fail: if r is an algebraic number such that Q(r) is not solvable by radicals, how would you get r in S? Of course, since you also have non-algebraic numbers in S, this is hardly a 'proof', more of a 'I would look at these kinds of numbers to try to settle the question in the negative'. === Subject: Given the radius of convergence for one series, I'm trying to find the radius for 2 simliar series Let f(z) = sum_k a_k*z^k be a formal power series with radius of convergence 1. Put s_n = a_0 + ... + a_n and t_n = (s_0 + ... + s_n)/(n+1). Let g(z) = sum_k s_k*z^k and h(z) = sum_k t_k*z^k. How would I show that the radius of convergence of h and g are both 1 as well? (The lim sup method doesnt seem to work). Greg === Subject: Re: Given the radius of convergence for one series, I'm trying to find the radius for 2 simliar series >Let f(z) = sum_k a_k*z^k be a formal power series with radius of >convergence 1. Put s_n = a_0 + ... + a_n and t_n = (s_0 + ... + >s_n)/(n+1). >Let g(z) = sum_k s_k*z^k and h(z) = sum_k t_k*z^k. >How would I show that the radius of convergence of h and g are both 1 >as well? (The lim sup method doesnt seem to work). Some hints: Note that for any epsilon > 0, there is C such that |a_k| < C (1+epsilon)^k for all k. What does that say about |s_k|? For the other direction, note that a_n = s_n - s_{n-1}. Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: What is C[[x]] (generating functions) : algebra structure I have a problem in combinatorics (chapter is generating functions) where f(x) = sum_{x>=0} a_n x^n is in C[[x]]. What is C[[x]]? I have to show that composition of two f,g in C[[x]] is again in C[[x]] if the constant term of g is 0. Our professor defined this structure in class but I can't find the definition. Any help on the definition of this structure is greatly apprecia. Also, what are WEIGH generating functions? === Subject: Re: What is C[[x]] (generating functions) : algebra structure NNTP-Posting-User: [DNl+kfRPf6mkEI2haabWc7pkPCvSlQMj] > I have a problem in combinatorics (chapter is generating functions) > where f(x) = sum_{x>=0} a_n x^n is in C[[x]]. > What is C[[x]]? Ring of formal power series. Elements are power series in x with coefficients in C, not necessarily convergent. > I have to show that composition of two f,g in C[[x]] is again in C[[x]] > if the constant term of g is 0. > Our professor defined this structure in class but I can't find the > definition. > Any help on the definition of this structure is greatly apprecia. > Also, what are WEIGH generating functions? Michael A. Van Opstall Padelford C-113 opstall@math.washington.edu http://www.math.washington.edu/~opstall/ === Subject: Re: What is C[[x]] (generating functions) : algebra structure Visiting Assistant Professor at the University of Montana. >I have a problem in combinatorics (chapter is generating functions) >where f(x) = sum_{x>=0} a_n x^n is in C[[x]]. >What is C[[x]]? Usually, power series on nonnegative powers of x. Like polynomials with coefficients in C, except they are allowed to have infinitely many nonzero monomials. === Subject: Re: What is C[[x]] (generating functions) : algebra structure > I have a problem in combinatorics (chapter is generating functions) > where f(x) = sum_{x>=0} a_n x^n is in C[[x]]. > What is C[[x]]? > I have to show that composition of two f,g in C[[x]] is again in C[[x]] > if the constant term of g is 0. > Our professor defined this structure in class but I can't find the > definition. > Any help on the definition of this structure is greatly apprecia. > Also, what are WEIGH generating functions? C[[x]] are simply formal power series, i e you do not care for convergence. Weigh? Just ask him (as you could do for the first Q), may be he says: 'put some factors at the coefficients'. Hm ... there is no shame to ask questions in lectures ... === Subject: looking for smooth function Hello sci.math, I've got an array size 100 of integer values (range: 0-5). Each plot in the array represents a 1ms time window. I currently have these graphed as stairs in MatLab (which looks like a bar graph). I want to make this function smooooooth, but i'm not sure of a method to apply to it. What steps should I take to complete this? Dustin === Subject: Express As Single Fraction How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc and (m^2 + 2)/(m^2 + m) - (m - 2)/m === Subject: Re: Express As Single Fraction >How do I do this? >Express the following as a single fraction: >4/3ab - 5/6bc Multiply the first term by 2c/2c and the second by a/a. >and >(m^2 + 2)/(m^2 + m) - (m - 2)/m Note that the denominator of the first term is m*(m+1). Use the same approach described above. <> === Subject: Re: Express As Single Fraction >How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc > Multiply the first term by 2c/2c and the second by a/a. I'm obviously doing it wrong but that appears to leave two different denominators. I thought we were trying to get a common one? === Subject: Re: Express As Single Fraction > How do I do this? > Express the following as a single fraction: > 4/3ab - 5/6bc > (m^2 + 2)/(m^2 + m) - (m - 2)/m You do it the same way you do it for fractions in arithematic. The general formula is derived thus a/b + r/s = as/bs + br/bs = (as + br)/bs === Subject: Re: Express As Single Fraction > How do I do this? > Express the following as a single fraction: 4/3ab - 5/6bc > (m^2 + 2)/(m^2 + m) - (m - 2)/m You do it the same way you do it for fractions in arithematic. > The general formula is derived thus > a/b + r/s = as/bs + br/bs = (as + br)/bs Yep, I understand the basic priniciple, but I just don't know how to put it in practise with these types of fractions. === Subject: Re: Express As Single Fraction > How do I do this? > Express the following as a single fraction: > 4/3ab - 5/6bc > and > (m^2 + 2)/(m^2 + m) - (m - 2)/m (1) find a common denominator. The least common denominator is a good one to use. (2) convert each fraction to an equivalent fraction, all having the same (common) denominator found in step 1. (3) Add (or subtract) numerators and put the result over the common denominator from step 1. (4) Reduce the result to lowest terms. Note that if you have used the least common denominator, the fraction may already be in lowest terms. === Subject: Re: Express As Single Fraction > How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc (1) find a common denominator. The least common denominator is a > good one to use. What, for example in the first one, is the lowest common denominator? Is it (3ab)(6bc)? If it is, do I then multiply that out? If not, what is it? === Subject: Re: Express As Single Fraction How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc (1) find a common denominator. The least common denominator is a > good one to use. > What, for example in the first one, is the lowest common denominator? Is it > (3ab)(6bc)? If it is, do I then multiply that out? If not, what is it? 6abc = (3ab)(2c) = (6bc)(a), so 6abc is a common multiple of 3ab and 6bc. Since (2c) and (a) have no common factor greater than 1, nothing can be left out of 6abc and still have a common multiple of 3ab and 6bc, so 6abc is the least common multiple. === Subject: Re: Express As Single Fraction >How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc > (1) find a common denominator. The least common denominator is a >> good one to use. > What, for example in the first one, is the lowest common denominator? > Is it (3ab)(6bc)? If it is, do I then multiply that out? If not, what > is it? Factorize all denominatars as much as possible, including numbers: 3ab = 3*a*b 6bc = 2*3*b*c The lowest common denominator is the lowest common multiple of the denominators. To get it, take all factors raised to the greatest exponent that appears. In this case, lcm(3ab, 6bc) = 2*3*a*b*c = 6abc Then multiply and divide each fraction by the quotient between the common denominator and its denominadtor: 4/(3ab) - 5/(6bc) = 4*(2c)/((3ab)*(2c) - 5*a/((6bc)*a) = (8c - 5a)/(6abc) -- Ignacio Larrosa Ca.96estro A Coru.96a (Espa.96a) ilarrosaQUITARMAYUSCULAS@mundo-r.com === Subject: Re: Express As Single Fraction >How do I do this? Express the following as a single fraction: 4/3ab - 5/6bc > (1) find a common denominator. The least common denominator is a >> good one to use. What, for example in the first one, is the lowest common denominator? > Is it (3ab)(6bc)? If it is, do I then multiply that out? If not, what > is it? > Factorize all denominatars as much as possible, including numbers: > 3ab = 3*a*b > 6bc = 2*3*b*c > The lowest common denominator is the lowest common multiple of the > denominators. To get it, take all factors raised to the greatest exponent > that appears. In this case, > lcm(3ab, 6bc) = 2*3*a*b*c = 6abc > Then multiply and divide each fraction by the quotient between the common > denominator and its denominadtor: > 4/(3ab) - 5/(6bc) = 4*(2c)/((3ab)*(2c) - 5*a/((6bc)*a) = (8c - 5a)/(6abc) === Subject: consecutive composite integers Examining a table of factors and primes, I found that for any sequence of consecutive composite numbers there is always one integer that has a prime factor larger than any other prime factor of any of the other integers. Further, this prime is not raised to any power. My question is: Is this true for all consecutive composite sequences and if so, is there a proof? (Here's an example: 1500, 1501, ... 1509. The last integer has the prime factor 503.) === Subject: Re: consecutive composite integers > Examining a table of factors and primes, I found that for any sequence > of consecutive composite numbers there is always one integer that has > a prime factor larger than any other prime factor of any of the others Nice conjecture! It is equivalent to saying (more neatly perhaps) that in any adjacent sequence of numbers, the largest prime factor occurs only once. It seems obviously true, though I can't see a slick proof off-hand. I'm sure there must be one. It is possible to produce a heuristic demo that can doubtless be turned into a formal proof with effort. Suppose your two largest equal prime factors are P, and we may as well put them at the ends of the interval WLOG. Then we have an interval of length P which must be filled up by factors less than P. This would mean the P interior numbers have to be removed one-by-one by ditching the evens, then the 3-multiples, then the 5-multiples, and so on up to P. But we can remove at most (1/2)*(2/3)*(4/5)*(6/7)*...*(1 - 1/P) this way; and a quick heuristic integral integral shows this to be 1/(log P). So the most numbers we can reduce to by removing those with (even at least one!) small prime factor is one log-Pth of the lot, and the lot is of size P. That's P/logP. Nowhere near zero or one. So it can't be done... not by a huge amount! Nice question though. -------------------------------------------------------------- -------------- -- Bill Taylor W.Taylor@math.canterbury.ac.nz -------------------------------------------------------------- -------------- -- Chebychev said it -- I'll say it again; There is always a prime between n and 2n. -------------------------------------------------------------- -------------- -- === Subject: Re: consecutive composite integers >Examining a table of factors and primes, I found that for any sequence >of consecutive composite numbers there is always one integer that has >a prime factor larger than any other prime factor of any of the other >integers. Further, this prime is not raised to any power. My question >is: Is this true for all consecutive composite sequences and if so, is >there a proof? >(Here's an example: 1500, 1501, ... 1509. The last integer has the >prime factor 503.) How does the Further,... apply to this example: 8, 9? Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: Re: consecutive composite integers of consecutive composite numbers there is always one integer that has >a prime factor larger than any other prime factor of any of the other >integers. Further, this prime is not raised to any power. > How does the Further,... apply to this example: 8, 9? Perhaps he intended maximal sequence, 8,9,10 has 5 as max. However the maximal sequences 4 and 12 have 2 squared and the maximal sequence 18 has 3 squared. Thus the conjecture needs be limi to maximal sequences of composite numbers longer than 1. === Subject: Re: consecutive composite integers >>Examining a table of factors and primes, I found that for any sequence >>of consecutive composite numbers there is always one integer that has >>a prime factor larger than any other prime factor of any of the other >>integers. Further, this prime is not raised to any power. >> How does the Further,... apply to this example: 8, 9? >Perhaps he intended maximal sequence, 8,9,10 has 5 as max. But the example he gave was 1500, 1501, ... 1509 which is not maximal. Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: Re: consecutive composite integers >Examining a table of factors and primes, I found that for any sequence >of consecutive composite numbers there is always one integer that has >a prime factor larger than any other prime factor of any of the other >integers. Further, this prime is not raised to any power. > How does the Further,... apply to this example: 8, 9? >>Perhaps he intended maximal sequence, 8,9,10 has 5 as max. > But the example he gave was 1500, 1501, ... 1509 which is not maximal. Also, the largest prime factor of a number in that range is 751, not 503. The conjecture still holds, but not for the reason given. -- Dave Seaman Judge Yohn's mistakes revealed in Mumia Abu-Jamal ruling. === Subject: Re: Did mathematicians know? well, isn't this teensy duality the same, for any proof that one hasn't actually read, all the way through (or to the point where one can see it through, already) ?? > you're saying that the L-wing thing is just an argument > *about* an actual (R-wing) proof? --les ducs de Buffet et Schulz (R&D Chair Assoc.Intl.); vote NONE OF THE BELOW on Trickier Dick Cheney's California Recall/e-Dereg! http://larouchepub.com http://members.tripod.com/~american_almanac/ === Subject: Re: The Bible Code it's not even wrong. it's just simple numbertheory -- skipcodes are that, and they were apparently used by (some?) Torah writers/copyists to ensure accuracy, as with the old CRC in 8-bit communications programs. I read taht they summed the letters on every 70th, or skipped to every 70th, or some thing. the computer can be set to find any message in any ring of an alphabet, and Drosnin et al know this ... or maybe they can't learn it, not because they're dumb. there was ambiguity in _The Bible Code_ taht he ignored, like with the variant translations and the fact that Old Hebrew has no vowels. repeat, _War and Peace_ or just the 26 letters in any order can be used with the infinite set of co-prime skips, with teh resulting hits being further massaged into some m by n array (or what ever). >FAILED. Is this accurate? And does this say something about the New Testament >and the belief in a Christ figure? --les ducs de Buffet et Schulz (R&D Chair Assoc.Intl.); vote NONE OF THE BELOW on Trickier Dick Cheney's California Recall/e-Dereg! http://larouchepub.com http://members.tripod.com/~american_almanac/ === Subject: Re: The Bible Code > it's not even wrong. it's just simple numbertheory -- > skipcodes are that, and they were apparently used > by (some?) Torah writers/copyists to ensure accuracy, > as with the old CRC in 8-bit communications programs. > I read taht they summed the letters on every 70th, > or skipped to every 70th, or some thing. > the computer can be set to find any message > in any ring of an alphabet, and Drosnin et al know this ... or > maybe they can't learn it, not because they're dumb. > there was ambiguity in _The Bible Code_ taht he ignored, > like with the variant translations and the fact that > Old Hebrew has no vowels. > repeat, _War and Peace_ or just the 26 letters in any order > can be used with the infinite set of co-prime skips, > with teh resulting hits being further massaged > into some m by n array (or what ever). >FAILED. Is this accurate? And does this say something about the New Testament >and the belief in a Christ figure? > --les ducs de Buffet et Schulz (R&D Chair Assoc.Intl.); > vote NONE OF THE BELOW > on Trickier Dick Cheney's California Recall/e-Dereg! > http://larouchepub.com > http://members.tripod.com/~american_almanac/ A defective theory when applied does neither prove or disprove a hypothesis. The Code stuff has been applied successfully to Moby Dick to predict moderns events with Astounding accuracy. (NOT!) rj Pease === Subject: Re: Re fermat by Tomas what is found at your site is known as Sophistry. the fact that Fernat's Last Theorem is negative is not problem, just as proofs (of neg or pos statements) by contradiction are good. of course, three per cent is rational by definition. Negative statements about numbers are unverifiable. Take the definition of an irrational as a number that is not rational, where being rational means having periodic decimal expansion. Suppose someone wants to verify that %3 is irrational. Since the indirect proof is out he computes its decimal expansion to the trillionth digit and, satisfied that no evidence of periodicity looms on the horizon, declares that %3 is irrational. A mischievous fellow quickly forms a periodic decimal whose first period is that first trillion > http://www.users.bigpond.com/pidro/home.htm --les ducs de Buffet et Schulz (R&D Chair Assoc.Intl.); vote NONE OF THE BELOW on Trickier Dick Cheney's California Recall/e-Dereg! http://larouchepub.com http://members.tripod.com/~american_almanac/ === Subject: A polynomial problem Hi all, I'm trying to prove the following theorem: Let P be a polynomial with real coefficients such that P(x) >=0 for every real x. Then, there are polynomials R and S such that P(x) = R^2(x) + S^2(x) for every complex x. It's easy to see that the degree of P must be even. If r is a real root of P, then the restriction of P to the reals has an absolute minimum at r and, from the differentiability of P, it follows there's an even number k such that the k-1 first derivatives of P vanish at r and the k_th is positive. Therefore, the k-1 derivatives admits the root r with multiplicity 1, which implies P admits r as a rooth with multiplicity k. So, we see every real root of P, when they exist, must have an even multiplicity (I think we could come to this same conclusion a bit faster, considering only the continuity of polynomial functions). Corollary - If all of the roots of P are real, then, P = Q^2 for some polynomial Q. So, for this particular case the theorem has just been proved. To prove the theorem, for the general case, I tried to use mathematical induction. It didn't work, that's why I'm asking for help. What I did is as folows: the previous paragraph, it's also enough to cover the case of even-degree polynomials with real coefficients and no real roots. It's well known that every monic trinomial T of the 2nd degree that satisfies such conditions can be written as T(x) = (x-a)^2 + C^2, where a and C<>0 are real. Therefore, for such trinomials the theorem holds trivially. Now, suppose there's a natural k such that the theorem holds for i=1,...k-1 for every 2i-degree polynomial with real coefficients and no real roots. If P is a 2k-degree polynomial with these same properties, then at some (or several) real r's the restriction of P to the reals attains an absolute minimum m>0. This implies that, for every real x, the polynomial P-m is non-negative, has one (or several) real root(s) and (i) P(x) - m = (x-r_1)^p1 *...(x-r^_n)^p_n * Q(x), where r_1, ..r_n are the real roots and the numbers p_1,...p_n are even. In addition, Q is monic, has even degree < 2k, has no real root and is strictly positive on the real line. By the induction assumption, the theorem holds for Q and, in virtue of (i), also holds for P-m. But now, to complete the induction, it remains to prove the theorem is good for P, in other words, it remains to prove that if the theorem holds for some polynomial P then it holds for P+m for every m>0. That's where I got stuck. Actually, I think I chose a very cumbersome way to prove the theorem, there certainly is a neater proof. Any suggestions are welcome. Amanda. === Subject: Re: A polynomial problem > I'm trying to prove the following theorem: > Let P be a polynomial with real coefficients such that P(x) >=0 for > every real x. Then, there are polynomials R and S such that P(x) = > R^2(x) + S^2(x) for every complex x. Show P factors over the reals as a product of irreducible quadratics times a product of squares of linear polynomials. Show that an irreducible quadratic is a sum of 2 squares. Show that a product of two sums of two squares is a sum of two squares. -- === Subject: Re: A polynomial problem >Hi all, >I'm trying to prove the following theorem: >Let P be a polynomial with real coefficients such that P(x) >=0 for >every real x. Then, there are polynomials R and S such that P(x) = >R^2(x) + S^2(x) for every complex x. >It's easy to see that the degree of P must be even. If r is a real >root of P, then the restriction of P to the reals has an absolute >minimum at r and, from the differentiability of P, it follows there's >an even number k such that the k-1 first derivatives of P vanish at r >and the k_th is positive. Therefore, the k-1 derivatives admits the >root r with multiplicity 1, which implies P admits r as a rooth with >multiplicity k. So, we see every real root of P, when they exist, must >have an even multiplicity (I think we could come to this same >conclusion a bit faster, considering only the continuity of polynomial >functions). >Corollary - If all of the roots of P are real, then, P = Q^2 for some >polynomial Q. So, for this particular case the theorem has just been >proved. >To prove the theorem, for the general case, I tried to use >mathematical induction. It didn't work, that's why I'm asking for >help. What I did is as folows: >the previous paragraph, it's also enough to cover the case of >even-degree polynomials with real coefficients and no real roots. It's >well known that every monic trinomial T of the 2nd degree that >satisfies such conditions can be written as T(x) = (x-a)^2 + C^2, >where a and C<>0 are real. Therefore, for such trinomials the theorem >holds trivially. Now, suppose there's a natural k such that the >theorem holds for i=1,...k-1 for every 2i-degree polynomial with real >coefficients and no real roots. If P is a 2k-degree polynomial with >these same properties, then at some (or several) real r's the >restriction of P to the reals attains an absolute minimum m>0. This >implies that, for every real x, the polynomial P-m is non-negative, >has one (or several) real root(s) and (i) P(x) - m = (x-r_1)^p1 >*...(x-r^_n)^p_n * Q(x), where r_1, ..r_n are the real roots and the >numbers p_1,...p_n are even. In addition, Q is monic, has even degree >< 2k, has no real root and is strictly positive on the real line. By >the induction assumption, the theorem holds for Q and, in virtue of >(i), also holds for P-m. But now, to complete the induction, it >remains to prove the theorem is good for P, in other words, it remains >to prove that if the theorem holds for some polynomial P then it holds >for P+m for every m>0. That's where I got stuck. >Actually, I think I chose a very cumbersome way to prove the theorem, >there certainly is a neater proof. I believe there is. The real roots all have even order and the complex roots come in conjugate pairs - this means there exists a polynomial F (with complex coefficients) such that P is the product of F and the complex conjugate of F... >Any suggestions are welcome. >Amanda. ************************ === Subject: non-Hausdorff homeomorphism to R^n is there a non-Hausdorff space locally homeomorphic to R^n? === Subject: Re: non-Hausdorff homeomorphism to R^n === Subject: non-Hausdorff homeomorphism to R^n >is there a non-Hausdorff space locally homeomorphic to R^n? No. I use theorem locally closed Hausdorff S ==> S Hausdorff S locally closed Hausdorff when for all p in S, some open U nhood p for which cl U is a Hausdorff subspace Let the non-Hausdorff space be S. As I don't know definition of locally homeomorphic I'll do my best to intuit what it means. If p in S, then there's some open U nhood p homeomorphic to an a nhood V of R^n about q, the image of p As R^n is normal, we can find a closed nhood K of q contained in V. Now the homeomorphic image of K is a closed Hausdorff nhood of p. Thus I hope I've shown S is locally closed Hausdoff, hence Hausdorff. ---- === Subject: Re: non-Hausdorff homeomorphism to R^n === > Subject: non-Hausdorff homeomorphism to R^n >is there a non-Hausdorff space locally homeomorphic to R^n? > No. I use theorem > locally closed Hausdorff S ==> S Hausdorff So what do you do about the real line with double origin? (Quotient of R x {0,1} by the smallest equivalence ~ with (x,0) ~ (x,1) for x =/= 0 ). -- === Subject: Re: non-Hausdorff homeomorphism to R^n >is there a non-Hausdorff space locally homeomorphic to R^n? Sure thing. Look for a current thread which mentions doubling points in one of the posts (I think by Simeon Stefanov). Not if n=0, though. Lee Rudolph === Subject: Open form for the integral of x^x dx by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h973a2W15776; I've been trying to find a generalized (open) formula for the integral of x^x dx.....does anyone know if it's been derived at all? Curious === Subject: real analysis: construct this set ... by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h974dnb19740; Can you construct a set E in [0, 1] s.t. for every open interval I in [0,1] m(I intersect E) > 0 & m(I intersect E^c) > 0 m is lebesgue measure E^c is the complement of E This is so tricky! I was thinking something with the generalized Cantor set but everything I'm trying isn't working. Any suggestions? Ideas? === Subject: Re: real analysis: construct this set ... >Can you construct a set E in [0, 1] s.t. for every open interval I in [0,1] m(I intersect E) > 0 & m(I intersect E^c) > 0 >m is lebesgue measure >E^c is the complement of E >This is so tricky! I was thinking something with the generalized Cantor set but everything I'm trying isn't working. Any suggestions? Ideas? I have previously pos an example of such a set, which is Borel measurable. Use the Cantor set idea, but with different sized parts removed from the intervals still in, and added to the intervals already removed. It can be done in terms of the digits to any base. -- This address is for information only. I do not claim that these views are those of the Statistics Department or of Purdue University. Herman Rubin, Department of Statistics, Purdue University hrubin@stat.purdue.edu Phone: (765)494-6054 FAX: (765)494-0558 === Subject: Re: real analysis: construct this set ... > Can you construct a set E in [0, 1] s.t. for every open interval I in [0,1] m(I intersect E) > 0 & m(I intersect E^c) > 0 > m is lebesgue measure > E^c is the complement of E A doubt. You say the Lebesgue measure. Are you implying that the construc set must be Lebesgue measurable? Or the problem somehow gives us a notion that, even if the wording Lebesgue measure is replaced by Lebesgue outer measure,it is impossible to find a Lebesgue immeasurable set satisfying the condition as the problem indicates? > This is so tricky! I was thinking something with the generalized Cantor set but everything I'm trying isn't working. Any suggestions? Ideas? === Subject: Re: real analysis: construct this set ... >> Can you construct a set E in [0, 1] s.t. for every open interval I in >[0,1] m(I intersect E) > 0 & m(I intersect E^c) > 0 >> m is lebesgue measure >> E^c is the complement of E >A doubt. You say the Lebesgue measure. Are you implying that the >construc set must be Lebesgue measurable? Or the problem somehow >gives us a notion that, even if the wording Lebesgue measure is >replaced by Lebesgue outer measure,it is impossible to find a >Lebesgue immeasurable set satisfying the condition as the problem >indicates? By saying m(...) where m is Lebesgue measure, it's clearly asking for measurable sets. As far as outer measure m^* is concerned, you can do a lot better: there is a (nonmeasurable) set E such that for every open interval I, m^*(E intersect I) = m(I) and m^*(E^c intersect I) = m(I). Robert Israel israel@math.ubc.ca Department of Mathematics http://www.math.ubc.ca/~israel University of British Columbia Vancouver, BC, Canada V6T 1Z2 === Subject: Re: real analysis: construct this set ... > Can you construct a set E in [0, 1] s.t. for every open interval I in [0,1] > m(I intersect E) > 0 & m(I intersect E^c) > 0 > m is lebesgue measure > E^c is the complement of E take away fat disjoint Cantor sets K1 and J1. Now from B2 (K1 U J1) take away fat disjoint Cantor sets K2 and J2. Continue, and set E = ... (If this is a homework problem and you use this hint, be sure to give credit to sci.math.) === Subject: dissolving Russel's Paradox by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97D3uP19205; I studied an alternative set theory which dissolves Russel's Paradox. In this theory, it is possible to get good theorems of ordinal number. More description about the set theory is available on my home page. http://boat.zero.ad.jp/~zbi74583/another02.htm I appreciate any comment about it. -------------------- @ 1.Axiom of Free Class. @ A. ma [A]A[A]B[A]x[A]y A ma x &@B ma y & A=B -> x=y This axiom means that any Atsumari makes only one class. A. el x[A]A[A]B ([A]a a el A <-> a el B) -> A=B This axiom means that an Atsumari is decided by its members. A.F [E]x{E]B ([A}a a el B <-> F(a)) & B ma x This is the Schema of comprehention axioms. Where A,B,C,...are variables for Atsumari, which means collection or set or pile in Japanese. a,b,c,...are variables for Class, [A] means all, [E] means exist, [E]! means exist only one, ma means makes, el means element, -> means then, <-> means equivalent, V means or, & means and, Atsu is an abbreviation of Atsumari ~ means negation, {a,b,c} means the Atsu which has members a,b,c 2.What does Free Class mean? @ [E]B a el B & B ma b means a el b in ZF (TR) For example if {a,c} ma b & {x,y} ma b are true, then a el {a,c} & {a,c} ma b so [E]B a el B & B ma b it means a el b in ZF. FC ZF {a,c} ma b corresponds a el b, c el b {x,y} ma b x el b, y el b 3. Russel's class [A]a a el R <-> ~([E]B a el B & B ma a) The right side of formula means ~(a el a) in ZF. This Atsu R makes Russel's Class r, so R ma r. Let a=r then, r el R <-> ~([E]B r el B & B ma r) If r el R is true, considering that R ma r is also true,then [E]B r el B & B ma r is true, then right side of formula is false. This is a contradiction. So, the following formulas are gotten. ~(r el R), [E]B r el B & B ma r. This conclusion means that the diagonal logic was dissolved. So, it is possible to think that 2^aleph(0)=aleph(0).@ === Subject: Re: dissolving Russel's Paradox > I studied an alternative set theory which dissolves Russel's Paradox. > In this theory, it is possible to get good theorems of ordinal number. > More description about the set theory is available on my home page > http://boat.zero.ad.jp/~zbi74583/another02.htm > I appreciate any comment about it. > .81@ 1.Axiom of Free Class. > .81@ Not using plain text in newsgroup makes reading difficult for some brousers. For example what does ^A@ mean? > A. ma [A]A[A]B[A]x[A]y A ma x &.81@B ma y & A=B -> x=y What does that mean? A makes for all A, for all B, for all x, for all y A makes x and ?? B makes y and A = B implies x = y Don't understand. What do you mean by 'A makes' ? > This axiom means that any Atsumari makes only one class. > A. el x[A]A[A]B ([A]a a el A <-> a el B) -> A=B > This axiom means that an Atsumari is decided by its members. > A.F [E]x{E]B ([A}a a el B <-> F(a)) & B ma x > This is the Schema of comprehention axioms. > Where A,B,C,...are variables for Atsumari, which means collection or set or pile in Japanese. > a,b,c,...are variables for Class, > [A] means all, [E] means exist, [E]! means exist only one, ma means makes, > el means element, -> means then, <-> means equivalent, > V means or, & means and, Atsu is an abbreviation of Atsumari > ~ means negation, {a,b,c} means the Atsu which has members a,b,c === Subject: a coloring problem by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97D48o19230; I studied a generalized coloring problem. The ordinary coloring problem is defined as follows. @ @@Place different colors on two vertices which are next each other in a plane graph. @@How many colors are necessary and enough? @ @@And new coloring problem is the following. @ @@A definition @@D.1. @@Place different colors on two vertices which are near each other in a plane graph. @@How many colors are necessary and enough? @ @@The term near is defined as follows. @@For different two vertices a and b,@either condition 1. or 2. is filled. @@c.1. a is next of b @@c.2. There are three paths of length 2 between a and b. @ @@c.1 and c.2 is represen as (1,1) and (2,3) respectively. @ @@If G is a plane graph and @@if edges are added between all pairs of vertices which satisfy (2,3)@in G, @@then this graph is written as Near_2,3(G) @ @@New problem is also defined as follows. @ @@Another definition @@D.2. @@What is chr(Near_2,3(G))? @@@@ where chr(x) means the chromatic number of x. @ I proved a theorem as follows. [ The@@7 colors theorem. ] @@T.7C.@@7 colors are necessary and enough. More description about this problem is available on my HP. @ http://boat.zero.ad.jp/~zbi74583/another02.htm === Subject: Re: The Octic x^8-x^7+29x^2+29 Revisi by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97D4OF19281; , By a stroke of luck, I managed to find the missing piece to the puzzle of how to solve the resolvent septic. So here is the complete solution: Given: x^8-x^7+29x^2+29 = 0 Then, x1=(1+(a-b-c-d+e-f-g))/8 x2=(1-(a-b-c-d-e+f+g))/8 x3=(1-(a+b-c+d+e-f+g))/8 x4=(1+(a+b-c+d-e+f-g))/8 x5=(1-(a+b+c-d+e+f-g))/8 x6=(1+(a+b+c-d-e-f+g))/8 x7=(1-(a-b+c+d-e-f-g))/8 x8=(1+(a-b+c+d+e+f+g))/8 where the 7 variables a,b,c,d,e,f,g are the SQUARE ROOTS (positive case) of 4v+1 and the v's are the roots of the septic: 8903+47647v+39672v^2+7192v^3-522v^4-174v^5+v^7 = 0 (eq.3) with the solution: v=2(w^11+w^13+w^16+w^18)-2(w+w^12+w^17+w^28)-(w^2+w^5+w^24+w^ 27)+ (w^3+w^7+w^22+w^26)+(w^4+w^10+w^19+w^25)-(w^8+w^9+w^20+w^21) where w is ANY complex root of unity <>1 such that w^29=1. Note: Though there would be 28 such roots, the properties of these roots ensure that v will ONLY have 7 distinct values. I found the solution of v in Dave Rusin's website, and it's by P.Montgomery, though the solution wasn't used in the same way I used it. Eq.3 wasn't explicitly mentioned there but when I used the Integer Relations applet for a particular v, eq.3 popped out. It looked familiar and I realized i saw it before while trying to solve the resolvent (eq.2) of the prior post, namely: z^7-7z^6-2763z^5-19523z^4+1946979z^3+34928043z^2+119557031z- 3247^2=0 (eq.2) and by letting z=4v+1, we get the new septic: 8903+47647v+39672v^2+7192v^3-522v^4-174v^5+v^7 = 0 (eq.3) So there it is. It's so nice to have completion. :) By the way, do SOME solvable 12-deg polys need an 11-deg resolvent? --Tito === Subject: Re: Quaternion Extensions by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97D4L919274; >> I have recently extended the Quaternions to larger sets by requiring >> some (new) group elements to commute. In doing so, I found this process >> and its results to be very asthetic. For one, the law of association is >> regained. However, the algebra involved is no longer a division algebra, >> i.e. we may not always follow x = 0 or y = 0 from xy=0 (when x and y are >> certain elements taken from a linear combination of group vectors). Has this type of thing been done before and are its conclusions of >> interest? It's obvious that there exist extensions of the quaternions H, >eg H + H (direct sum), >or algebras of matrices with quaternion elements. You'd have to say what properties your extension has >before anyone could say if it is of interest. >I am neither refering to the ring of quaternion matrices nor to the >group >product... have sent you a copy of this work. >Apologies for not replying to your email ... lectures have just begun. >My point was that you seemed surprised to find that >there were algebras extending the quaternions, >and I no that this wasn't too surprising. >So the fact that you have construc such an algebra >could not be considered interesting in itself -- >any interest would have to lie in the special properties of the algebra. >-- >Timothy Murphy >e-mail: tim /at/ birdsnest.maths.tcd.ie >(all email over 80k dispatched to /dev/null) >tel: +353-86-2336090, +353-1-2842366 >s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland Absolutely no need to apologize for not having replied yet; it is good to know you recieved it, as I now asume to be the case. The group diagram picture I made on page 4 or 5 (I forgot) and its explanation in the text should tell a lot about the group's properties very quickly. By the way, the same process of extension (I call it reflection) can be used again and again to create more group elements, presumably proceeding to higher dimensions in the process- but Im not quite sure if this is somehow equivilant or to the procedure for extending Clifford Algebras (or, indeed, if my group is perhaps a Clifford algebra in disguise. Admit, I don't know enough about Clifford algebras at the momement and am currently checking this possibility myself). Note also that many types of groups can be reflec, but this does not always give rise to a new group. For example, the trivial group {1,-1} does not change after reflection (the complex trivial group {1,-1, i, -i} does). Creighton Dement === Subject: Chessboard knight metric? by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97E9gZ23741; >Take a chessboard (with or without infinetely many squares) let the >distance d((x_1,x_2),(y_1,y_2)) between two squares x and y of the >chessboard be defined as the minimum number of moves a knight takes >to reach y from x. >Is d a metric? Not trying to suggest that this is some new >question that hasn't been asked/answered before. Is there a general >formula for calculating d? More generally, the same question may be >asked for the other pieces (queen, king, knight, biship)? Actually, I >asked myself this question a few years ago. If I remember back to the >notes I took, I had something like (x_1-y_1, x_2-y_2)= (even number, >even number), then d(x,y) = even number. If (x_1-y_1, x_2-y_2)= (even >number, odd number), then d(x,y) = odd number. Finally, if (x_1-y_1, >x_2-y_2)= (odd number, odd number), then d(x,y) = even number. In other words, the same rules for adding natural numbers... === Subject: Re: Chessboard knight metric? >Take a chessboard (with or without infinetely many squares) let the >distance d((x_1,x_2),(y_1,y_2)) between two squares x and y of the >chessboard be defined as the minimum number of moves a knight takes >to reach y from x. >Is d a metric? With this distance, the triangular equation is obviously true, and that makes it a metric. > Not trying to suggest that this is some new >question that hasn't been asked/answered before. Is there a general >formula for calculating d? More generally, the same question may be >asked for the other pieces (queen, king, knight, biship)? Actually, I >asked myself this question a few years ago. If I remember back to the >notes I took, I had something like (x_1-y_1, x_2-y_2)= (even number, >even number), then d(x,y) = even number. If (x_1-y_1, x_2-y_2)= (even >number, odd number), then d(x,y) = odd number. Finally, if (x_1-y_1, >x_2-y_2)= (odd number, odd number), then d(x,y) = even number. In other >words, the same rules for adding natural numbers... > === Subject: Re: Pointless by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97E9jb23746; >mathedman scribbled the following >on comp.lang.c: >> Why is this being discussed in comp.lang.c??? >Obviously because IT IS FULL OF JEWS!!! Jews are taking over >comp.lang.c because their greedy grubby need to take over everything is >finally seeping into the C language. Next thing you know they will be >trying to rewrite the standard. The entire reason for my low IQ and >inability to succeed in life can be attribu to jews. If it wasn't >for all the damn JEWS in science I wouldn't have to study! They keep >taking all the women too, being all nice and treating them with >respect and making me look like a complete ass. They took all the >jobs, now there is no point even looking for one. All I can do is sit >around all day filled with self pity and loathing for the damn JEWS who >did this to me. I hate my life and its all the fault of the Jew! >> YOU are a total idiot. >I thought he was being sarcastic. >-- >/-- Joona Palaste (palaste@cc.helsinki.fi) ---------------------------| Kingpriest of The Flying Lemon Tree G++ FR FW+ M- #108 D+ ADA N+++| >| http://www.helsinki.fi/~ palaste W++ B OP+ | >----------------------------------------- Finland rules! ------------/ >It sure is cool having money and chicks. > - Beavis and Butt-head If he was, then he is very bad at it. === Subject: Re: Quaternion Extensions by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97FaaV30213; > I have recently extended the Quaternions to larger sets by requiring > some (new) group elements to commute. In doing so, I found this process > and its results to be very asthetic. For one, the law of association is > regained. However, the algebra involved is no longer a division algebra, > i.e. we may not always follow x = 0 or y = 0 from xy=0 (when x and y are > certain elements taken from a linear combination of group vectors). Has this type of thing been done before and are its conclusions of > interest? >>It's obvious that there exist extensions of the quaternions H, >>eg H + H (direct sum), >>or algebras of matrices with quaternion elements. >>You'd have to say what properties your extension has >>before anyone could say if it is of interest. >>I am neither refering to the ring of quaternion matrices nor to the >group >>product... have sent you a copy of this work. >>Apologies for not replying to your email ... lectures have just begun. >>My point was that you seemed surprised to find that >>there were algebras extending the quaternions, >>and I no that this wasn't too surprising. >>So the fact that you have construc such an algebra >>could not be considered interesting in itself -- >>any interest would have to lie in the special properties of the algebra. >>-- >>Timothy Murphy >>e-mail: tim /at/ birdsnest.maths.tcd.ie >>(all email over 80k dispatched to /dev/null) >>tel: +353-86-2336090, +353-1-2842366 >>s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland >Absolutely no need to apologize for not having replied yet; it is >good to know you recieved it, as I now asume to be the case. The >group diagram picture I made on page 4 or 5 (I forgot) and its >explanation in the text should tell a lot about the group's >properties very quickly. By the way, the same process of extension > (I call it reflection) can be used again and again to create more > group elements, presumably proceeding to higher dimensions in the >process- but Im not quite sure if this is somehow equivilant or to >the procedure for extending Clifford Algebras (or, indeed, if my >group is perhaps a Clifford algebra in disguise. Admit, I >don't know enough about Clifford algebras at the momement and am >currently checking this possibility myself). Note also that many >types of groups can be reflec, but this does not always give rise >to a new group. For example, the trivial group {1,-1} does not change > after reflection (the complex trivial group {1,-1, i, -i} does). >Creighton Dement by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) with ESMTP id h97G9do32618 id 1A6uP0-0003DA-6d include it with any abuse report 12]
 



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=== Subject: Re: The ... spacetime; answer to critic. by support1.mathforum.org (8.11.6/8.11.6/The Math Forum, $Revision: 1.9 primary) id h97JmJl15824; I know it is a bit stupid, but 1> how do you prove that a discrete topology is metrizable? 2> X is an set of all positive integers and T={{},{1,2,3,4...},{2,3,4...},{3,4...},{4...},...} Why is (X,T) not metrizable? >
 As a topological space spacetime is metrizable, but one 
does
not,
> in general, look at any particular metric (in the
topological
sense)
> on it.
Why Severian thinks that this Hausdorf topology on Space-Time
> is adequate to its physical sence and geometrical structure?
I care nothing for physical sence (sic). All I was doing was
pointing
> out that the term metric was being used in two different ways
> (like many words in mathematics).
Do you mean as two
ways:::::::::::::::::::::::::::::::::::::::::::::::::::::::
> ### (pseudo-)Riemann metric -- quadratic form
> and
> ### metric (distance)
> ?
Yes, they're different, but the first is applicable only to
manifolds.
Yes, I know that, but the original poster was confused by
these two
> distinct concepts having the same word.
>Of course the two concepts are rela this way. So? The
> original poster was talking about one version of metric
> in terms of the definition of the other version - that's
going
> to cause confusion, regardless of the fact that the two
> are rela, so pointing out that they are two different
> things seems like a good idea.
>The original poster. In the original question. Where he said
something
>about metrics that applied to one version, then asked about
what
>he said in re an instance of the other version.
>And note how these concepts are rela and how it can be
applied to
S.T.
>>seems also a good idea...
>More precisely:
The standard topology of Euclidean space is induced by metric.
You are failing to specify which usage of the term metric you
are using
> here.
>>Directly, I used the metric (distance).
>>But the Euclidean distance is a partial case of Riemann
distance,
>>so not important which I use distance or quadratic form.
>The standard topology of Minkowski space isn't.
Minkowski space is metrizable.
>>Himmel! ### Not by Minkowski metric ! ! !
>He didn't say it _was_ metrizable by the Minkowski metric.
>He said it was metrizable. It is.
>You said The standard topology of Euclidean space is induced
>by metric. The standard topology of Minkowski space isn't.
>We assumed that induced by metric meant induced by
>some metric.
>What _did_ you mean by induced by metric??? If
>induced by metric means induced by Minkowski
>metric then the standard topology on euclidean
>space is _not_ induced by metric...
>>You implicitly defined on it
>>the standart (Hausdorf) topology of finite-dimension linear
space
>>and said that it's metrizable, as all finite-dimension
linear spaces!
>>Original question was NOT ABOUT SUCH TOPOLOGY,
>>but IS Minkowski A METRIC on the Space-Time? .
>>The answer is:
>>____________________________________________________________
_______
>>[ Minkowski metric on the Space Time ( dx0^2 -dx1^2 -dx2^2
-dx3^2 )
>>[ not leads to any metric (distance function) in classical
sence.
>That's correct. Several people have explained this already.
Nobody has
>disagreed with this.
>>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>The standard topology of Euclidean space is
> the only (non-trivial) topology invariant to motions
(rotation,
mirror, shift).
Is it? Proof?
>>Sorry, in general it isn't. I mistaken.
>>It's true that any non-one-point and non-discrete invariant
topology
>>is identical to standard IN ANY BOUNDED DOMAIN,
>Say _exactly_ what this means (and give a hint of the proof.)
>Seriously, I cant figure out what it means. Because I can't
>see what it means for a topology on a BOUNDED DOMAIN
>to be invariant under shifts, for one thing. Nor under
rotations,
>unless it happens that the domain is invariant under
rotations.
>>but at infinity exist some different cases...
>>Except standard topology, it may be some COMPACTIFIED
topologies.
>>One of them is like standard but accepts only bounded closed
subsets
>>(or, the same, only open subsets which are neighbourhoods of
infinity).
>>Is there another cases, I don't know yet.
>>I would ignore this fact a long time...
>The standard topology of Minkowski space is invariant but not
unique.
In Euclidean case, all smooth maps from R to the Space
are CONTINIOUS
> and may represent a point trajectory in Newtonian mechanics.
> In the Space-Time, all smooth maps R->M are continious
(in std. top.),
> but not all are physically allowed.
physically allowed!
>>This mean that the 4-speed is not space-like:
>>( d x / d tau )^2 >= 0
>>and that we have a correct time sign:
>>( d x0 / d tau ) >= 0
>What bull.
>>*** Anecdote:
>>enter expression: cos ( pi / 2 )
>>Syntax error!
>>enter expression: 1 * 0
>>Syntax error!
>>enter expression: 2 + 2
>>Syntax error!
>>enter expression: .8f.9b.90 .99.8c.89.8c
>>.8f.9b.90 is not an argument!
>>--
>>qq~~~~>/ / > /_/ /
>> ____/
>>

===

Subject: Re: The ... spacetime; answer to critic.
> I know it is a bit stupid, but
> 1> how do you prove that a discrete topology is metrizable?
Write down a metric for it
The simplest possible metric should give the discrete topology
...
> 2> X is an set of all positive integers and
> T={{},{1,2,3,4...},{2,3,4...},{3,4...},{4...},...} Why is
(X,T) not
> metrizable?
Is it Hausdorff?
--

===

Subject: Re: Chessboard knight metric?
by support1.mathforum.org (8.11.6/8.11.6/The Math Forum,
$Revision:
1.9 primary) id h97JmW515882;
>>Take a chessboard (with or without infinetely many squares)
let the
>>distance d((x_1,x_2),(y_1,y_2)) between two squares x and y
of the
>>chessboard be defined as the minimum number of moves a
knight takes
>>to reach y from x.
>>Is d a metric? Not trying to suggest that this is some new
>>question that hasn't been asked/answered before. Is there a
general
>>formula for calculating d? More generally, the same question
may be
>>asked for the other pieces (queen, king, knight, biship)?
Actually, I
>>asked myself this question a few years ago. If I remember
back to the
>>notes I took, I had something like (x_1-y_1, x_2-y_2)= (even
number,
>>even number), then d(x,y) = even number. If (x_1-y_1,
x_2-y_2)= (even
>>number, odd number), then d(x,y) = odd number. Finally, if
(x_1-y_1,
>>x_2-y_2)= (odd number, odd number), then d(x,y) = even
number. In other
words, the same rules for adding natural numbers...
Sorry for not quite completing the question above (even
though,
>perhaps, obvious):
>Is d a metric over the product space of whole/natural numbers
>(corresponding to two different cases of an infinite chess
board)
>or the restriction of the product space of natural numbers to
64 elements?
by support1.mathforum.org (8.11.6/8.11.6/The Math Forum,
$Revision:
1.9 primary) id h97JmTA15867;
A grammar would be
S -> BaB
B -> BB
B -> aBb
B -> bBa
B -> lambda
I doubt there is a way to prove it, or find a base case
>A grammar would be
>S -> BaB
>B -> BB
>B -> aBb
>B -> bBa
>B -> lambda
>I doubt there is a way to prove it, or find a base case
It's easy to see that B gives any string with the same number
of a's and b's, so we just need to show that if a string has
one more a's than b's it can be written as BaB.
Say s is such a string, and say s[n] is the initial substring
of s of length n. Now s = s[length(s)] has more a's than
b's, so there exists an n such that s[n] has this property.
Let N be the _smallest_ n such that s[N] has more a's
than b's. Then s[N-1] must have the same number of a's
and b's and the N-th character must be a, QED.
************************

===

Subject: Does Goldbach imply Reimann
by support1.mathforum.org (8.11.6/8.11.6/The Math Forum,
$Revision:
1.9 primary) id h97KV2u19406;
It is possible prove the Ternary Goldbach Conjecture (TGC) and
the Twin
Prime Conjecture (TPC) are true, if the Generalized Riemann
Hypothesis (GRH)
is true.
See
http://www.ams.org/era/1997-03-15/S1079-6762-97-00031-0/S1079-
6762-97-00031-
0.pdf
for the proof of GRH-->TGC.
Is there a similar paper for the converse? If the TGC or TPC
is true then,
the GRH or (RH) is true.
My question is can either of the following be proved?
TGC-->GRH
or
TPC-->GRH
John Washburn

===

Subject: Re: Does Goldbach imply Reimann
> It is possible prove the Ternary Goldbach Conjecture (TGC)
and the Twin
Prime
> Conjecture (TPC) are true, if the Generalized Riemann
Hypothesis (GRH) is
> true.
GRH implies twin primes? News to me.
> Is there a similar paper for the converse? If the TGC or TPC
is true
then,
> the GRH or (RH) is true.
Not to my knowledge.
--

===

Subject: Re: Class of computable functions
>Suppose I want a 'large' computably enumerable collection of
functions
>f_i : N --> N with the following properties:
>1. Each primitive recursive function is included.
>2. Each f_i is total by construction.
>3. Given i and n in N, there is a computable function time: N
x N --N which tells me that the value of f_i(n) will take at most
time(i,n)
>to compute by a turing machine or equivalent.
>['Take as long as you want, but PLEASE tell me when you will
be
>done!']
>4. The function time is computable in 'Ackermann + constant'
time,
>or at least it's behavior is boundedly nasty in some sense. :)
There was a paper 40 years ago somewhat along these lines. If
you want to be able to predict how long a computation will
take,
then you have severely restric the class of functions. Here
is the reference:
Robert W. Ritchie
Classes of predictably computable functions
Transactions of the American Mathematical Society,
vol. 106 (1963), pp. 139-173
It might help.
--Herb Enderton

===

Subject: Re: Class of computable functions
> I took a class in basic foundations and computability last
year, but
> there is a question that has been bothering me.
> Suppose I want a 'large' computably enumerable collection of
functions
> f_i : N --> N with the following properties:
> 1. Each primitive recursive function is included.
> 2. Each f_i is total by construction.
> 3. Given i and n in N, there is a computable function time:
N x N --N which tells me that the value of f_i(n) will take at
most time(i,n)
> to compute by a turing machine or equivalent.
> ['Take as long as you want, but PLEASE tell me when you will
be
> done!']
> 4. The function time is computable in 'Ackermann + constant'
time,
> or at least it's behavior is boundedly nasty in some sense.
:)
> I feel rather queasy about the prospects for this, but it
has been
> bothering me for too long. The basic theme is this: I want
to know
> worst case scenario computation time. Will I not get much
besides
> primitive recursive functions?
> Rex Butler
> PS I've heard the term 'strongly computable.' Is this rela?
take a look at http://members.ozemail.com.au/~chess3/tm1.html
Its 10 lines of code (actually a 5 state Turing Machine) and
there is no
proof if it terminates. Only 10 lines and no value for f_i.
In theory your class could be all well defined and well
behaved functions,
but in practice they will only be trivial.
Say you are nesting loops, then the invariants at each level
would have to
be combined into parallel equations, you have to solve all
enumerations
of possible equations, and show they are satisfied for each
loop to
terminate.
Even then the class of functions has no scope, here is a tiny
3 state TM
http://members.ozemail.com.au/~chess3/tm2.html you can
construct it easy
enough but how do you categorise what function it is? ~ binary
counter.
Herc