X-Message-Number: 14147 From: Date: Sun, 23 Jul 2000 07:46:46 EDT Subject: Re: Msg# 14128, continuity, distinguishability etc Re: continuity, distinguishability etc from: Robert Ettinger: > Again I take issue with this. "Same quantum state" can be a tricky and > misleading label. If (say) two atoms are widely separated in space, then they > ARE distinguishable both in principle and in practice. (Look at a track in a > cloud chamber.) (In addition, of course, a FULL designation of "quantum > state" for any system is beyond our current knowledge, and might even have to > account for the complete history of the cosmos, if interacting systems remain > entangled.) > If I recall well, space coordinates are included in the quantum state definition, so that two objects at two different places can't be in the same quantum state. Only bosons are able to pile up at the same place and so may be indistinguishable, this is what we get in a laser beam. Half spin matter particles must be paired into whole spin entity (bosons) before they can be put in the same state, because that coupling is very feeble, it work only near the absolute zero temperature, this is the so called Bose-Einstein condensate. Even so, the condensate is about the paired system, not the individual half spin elements it is made of. Entanglement is a multilinear process with at least time variable operators (rank two tensor quantum formalism).; At rank up to infinity every particle in the Universe is indeed coupled to any other, this is a mere philosophy statement as practical science can only recover a finite rank state. For short and in the cryonics frame, all particles are distinguishable and everything else is hair splitting. Yvan Bozzonetti. Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=14147