From: paul@mtnmath.UUCP (Paul Budnik)
Newsgroups: sci.physics
Subject: Re: Hidden variable theories, was: Uncertainty Princi
Date: 12 Sep 92 15:04:19 GMT
Organization: Mountain Math Software, P. O. Box 2124, Saratoga. CA 95070

In article <1992Sep12.020632.9597@galois.mit.edu>, jbaez@riesz.mit.edu (John C. Baez) writes:

> Your latest post confirms that we have no argument over facts, just
> massive disagreements about vocabulary, which reassures me that I can
> let the matter rest.

Good, but I think it will be worthwhile to confirm this by trying to state
the facts clearly.

	1. Bell's inequality is a mathematical result (it does not involve
	quantum mechanics) that any local theory must satisfy.

	2. Quantum mechanics predicts the equality is violated. It is possible
	to test this experimentally.

	3. In an experimental tests of Bell's inequality manipulations of a local
	polarizer must instantaneously influence results obtained by a distant
	observer or Bell's inequality cannot be violated.

	4. This influence is not detectable at the time it occurs but is
	detectable at a later time by comparing a series of polarizer angles
	and detections observed at both sites.

The arguments about this center on item 3 with item 4 being used to dismiss
its significance. Experimentally detectable influence, by standard definitions,
involves the transfer of information and, if it occurs instantaneously,
violates either causality or Lorentz invariance.

Do you disagree with item 3? 

> >I would appreciate some references. In everything I have read in respected
> >journals there is no disagreement that either causality or Lorentz invariance
> >is violated. There is a lot of garbage written in popular accounts
> >of this subject. 
> 
> See any book which explains the various axiomatic approaches to quantum
> field theory. ...  There
> are, in fact, two distinct notions of causality in quantum field
> theory, "microscopic causality," which is called "Local commutativity" on
> p. 597 of the book cited above, and another sort of causality
> sometimes called the "diamond property," also discussed on the same
> page.

Why is there any need to introduce new definitions of a term that has
a well established meaning? Of course you may need to introduce new
concepts that are variations or related to the traditional term, but
why redefine it in two different ways. Doesn't this make things
needlessly confusing and lead to pointless arguments?

> 
> >Regarding the rest of your message, there is no absolute contradiction
> >in quantum mechanic only some very unlikely predictions.
> 
> Unlikely, eh?  Care to state odds at which you'd bet some real money? 
> I'm already looking forward to 50 bucks from Dave Ring when his
> "solid evidence for supersymmetry" fails to materialize.  (Say - I
> forget when the deadline on this bet was!  I don't want to let him
> weasel out via indefinite postponement!)  I look forward to the day
> when an improved Aspect-type experiment rules out a Lorentz-invariant
> wavefunction collapse theory by giving a real violation of Bell's
> inequalities - but I'd look forward to it even more if I knew I would
> make some money off it!

I will be happy to bet you $50 that by the year 2005 there will be
substantial experimental evidence that there is a space-like separation
between correlated events that would otherwise violate Bell's
inequality. I think the odds are very much in my favor and you think
they are very much in you favor, so I would suggest an even wager is
appropriate.

Paul Budnik
Newsgroups: sci.physics