Dave-Platt%LADC@CISL-SERVICE-MULTICS.ARPA (Dave Platt) (02/08/86)
Concerning the discussions in this newsgroup of about a month ago, concerning particle-pair correlations... there have been a couple of articles in Science News recently on this topic, and interested Spacenetters may want to dig them up. A brief summary: experiments by Alain Aspect (U. of Paris-South, Orsay, France) seem to show that quantum-mechanical correlations do exist (see Science News 1/11/86, page 28). The big question now seems to be: are these phenomena a genuine example of "action at a distance" (a concept rejected by modern physics), or is there some form of real information-passing going on between the two particles in a pair (a "cue ball" on the pool table of physics, so to speak)? Jean-Pierre Vigier (Institut Henri Pointcare, Paris) is planning an experiment to test a theory largely associated with the name of David Bohm of Birbeck College (U of London, England) which invokes a "cue ball" (information carrier) in the form of a quantum potential (analogous in some respects to an electrical or gravitational potential). The Bohm potential is derived from the basic equation of quantum mechanics (The Schrodinger equation). In the case of quantum-mechanical correlations, the Bohm potential acts to provide the information contact between the particles that maintains the correlation. The interesting thing, according to the Bohm theory, is that the quantum potential must propagate itself faster than "c"... in fact it propagages at 7.57c! Thus, the potential would violate the precept of special relativity that says that no information can travel faster than "c"... but it savs a more important principle: the reductionism of physics (the ability to reduce an object under study to its parts, and study them in isolation). If action-at-a-distance does actually occur, apparently reductionism goes out the window, and one can have a system whose properties do not result from the sum of its parts. (from Science News v129, 2/1/86).