Quantum nonseparability,
coherence,
spatial order...

Date: Mon, 11 Dec 1995 13:01:20 -0800
From: David Finkelstein <df4@prism.gatech.edu>
Reply to: quantum-d@teleport.com
To: quantum-d@teleport.com
Subject: QUANTUM-D: quantum nonseparability, coherence, spatial order

1. Quantum nonseparability (= entanglement) is a consequence
of coherence for the case of composite (product) systems.

2. I suppose that spacetime itself is a macroscopic coherent
mode of a more general structure, as a superconductor is a 
mode of a polyatomic crystal. I tentatively dub this oldest 
of the supercondensates "supercrystal", to go with superconductor 
and superfluid. It is characterized by perfect defect-mobility
(infinite defect-mobility with Meissner effect) and a transition 
temperature of hundreds of GeV's (at least).

This refers to a speculative theory still under development.

3. I do not know how to apply quantum theory to the universe as a 
whole (and in particular to the big bang). One of the prime tenets
of quantum theory is that its operators represent actions that 
are possible in principle. A sharp determination of the universe 
(by someone inside it, it goes without saying) is impossible in 
principle. A quantum theory that allows the kind of determinations 
that we can make in principle and only those is still beyond my ken. 
It would seem to require an extension of Dirac transformation theory
from whole closed systems to partially open systems. As far as I know
a theory of this kind is not yet under development.