X-Message-Number: 3778 Date: Wed, 1 Feb 1995 21:40:38 -0800 From: John K Clark <> Subject: SCI.CRYONICS Uploading -----BEGIN PGP SIGNED MESSAGE----- "Steven B. Harris" <> Wrote: >I cannot see what exchange forces (Pauli forces) have to do >with anything I don't think exchange forces have anything to do with consciousness, I only mentioned them to demonstrate that quantum particles have no individuality, but as long as were on this tangent ; Pauli's exclusion principle is very important ,it's the basis of the periodic table, but it's only one example of exchange forces . >such forces operate only between "identical" members of one >class of partic-les (fermions), and but not "identical >members" of the other class. [...] condensation into >the same quantum state in the absence of exchange forces >between bosons ... Exchange Forces do operate between bosons but unlike the Pauli exclusion principle that acts only on fermions and is repulsive, on bosons exchange forces are weak and a force of attraction not repulsion. Exchange forces are what causes Bose-Einstein condensation that you were referring to. We must use The Identity Of Indiscernibles to derive the fact that there are indeed two classes of particles. Experimentally we can't measure the quantum wave function F(x) of a particle we can only measure the intensity of the wave function [F(x)]^2 because that's probability and probability we can measure . P(x) =[F(x)]^2 is the probability of finding two particles x distance apart. Now let's exchange the position of the particles, the distance between them was x1 - x2 = x is now x2 - x1 = -x . The Identity Of Indiscernibles tells us that because the two particles are the same no measurable change has been made , no change in probability ,so P(x) = P(-x) . From this we see that [ F(x) ]^2 = [ F(-x)]^2 so the Quantum wave function can be an even function [ F(x) = +F(-x) ] or an odd function [F(x) = -F(-x) ] , remember (-1)^2 = (+1)^2 =1. Both solutions have physical significance, particles with integer spin , bosons, have even wave functions, particles with half integer spin , fermions, have odd wave functions . If we put two fermions like electrons in the same place then the distance between them x is zero and because they must follow odd wave functions , F(0) = -F(0) but the only number that is it's own negative is zero so F(0) =0 . What this means is that the wave function goes to zero and [F(x)]^2 goes to zero , thus the probability of finding two electrons in the same spot is zero and that is The Pauli Exclusion Principle. What all this has to do with survivability, immortality or uploading is left as an exercise for the reader. >being quantum-identical in quantum mechanics does *not* >guarantee identical behavior. Quite true, quantum mechanics is after all a non deterministic theory. > two identical brains become quantum non-identical with great >rapidity That would be true even without quantum mechanics. Nobody has ever proven that quantum effects change the way the brain functions at all but it probably has a subtle, negative, effect by introducing a little randomness. There's not a shred of doubt that the environment ( sense input, drugs, a blow to the head) can alter the operation of the brain and the effect can be huge. Drinking a cup of coffee will change you more than quantum non deterministic events ever will. > Please note that this is the same problem that all of us are >faced with every single day. Absolutely true. It doesn't bother us now so I see no reason it will bother us in the future. I could change my mind about that but if I do it will almost certainly be because of computation or changes in my environment and not because of quantum effects in my brain . John K Clark -----BEGIN PGP SIGNATURE----- Version: 2.6.i iQCzAgUBLzBrK303wfSpid95AQFAtwTvX2//kKPQVoLoOkn5Am20t1xoP1MwI2H5 yiOVCkxuegpb1NEjL9j3vyL9t2/6wXj8Ub4IrD4GQZ6waQA1C4jpSONG9oQ8XG6x AFZMxRe25qBaNLvJBCqKpS3as5JG7MN9ztHj9Bi6fwukAL52gFjEDP6Mt9CsX8C6 a7l9dxYQhQUgltwUN74dUnULrL4WMfCj2XxQ3UVt0T0U1BbkUWY= =kFl7 -----END PGP SIGNATURE----- Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=3778