# Talk:Bell's theorem

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## Two questions

Absolute signs are not present in the inequalities. This had me confused for a while. The statement without inequalities are, on the face of things, stronger. Should we have inequalities? Original references and introductory QM texts I might add as references (below) have them. If not, then some explanatory remarks are warranted for. YohanN7 (talk) 09:49, 29 April 2016 (UTC)

Is it desirable to have sample hidden variable theories? The ones I have in mind are

1. Spin 12 one-particle theory that fails to reproduce predictions of QM. (From introductory QM texts.)
2. Spin 12 one-particle theory that reproduces QM predictions. (From Bell's original paper.)
3. Spin 12 two-particle theory that fails to reproduce predictions QM. (From introductory QM texts.) Bell's trick that works in one-particle theory doesn't work for two-particle theory because it is non-local.

I believe that this could be illustrative. I estimate it would occupy about one screen. YohanN7 (talk) 09:49, 29 April 2016 (UTC)

About the absolute values, I am neutral.
About the sample hidden variable theories, I like this idea. Boris Tsirelson (talk) 20:28, 29 April 2016 (UTC)

## Is this site safe?

[http://www.ipod.org.uk/reality/reality_entangled.asp Quantum Entanglement, by Dr Andrew H. Thomas]. [http://www.faculty.umb.edu/gary_zabel/Courses/Parallel%20Universes/Texts/Quantum%20Entanglement.htm Archived version]. Includes a simple explanation of Bell's Inequality. This site needs to be checked for safety. I went to the first one (ipod.org) and an obvious virus is involved. It might have come from another source--a few hours earlier I had logged into a server in a department store while a friend did some shopping.--Guy vandegrift (talk) 14:07, 10 June 2016 (UTC)

Indeed, it redirects to something irrelevant. Boris Tsirelson (talk) 19:07, 10 June 2016 (UTC)
When I went to the ipod.org site, my laptop froze and it looked like a virus. By the way, I do like the link to Doctor Chinese that I believe the same editor added. One of his (Dr Chinese's) other "calculations" (not linked from Wikipedia) proposes negative probability, but I think his intent was to be humorous. Such humor would be inappropriate on Wikipedia though. Should I delete one or both the external links that I de-wikied? I am afraid to take my laptop to those sites.--Guy vandegrift (talk) 01:47, 11 June 2016 (UTC)
I finally found a library computer where I can click external links with minimal risk. The ipod.org site is dysfunctional so I removed it. I have reservations about the other site (Quantum Entanglement, by Dr Andrew H. Thomas). It appears to be legitimate but a bit long winded. I have no objection to anybody removing it.--Guy vandegrift (talk) 15:00, 13 June 2016 (UTC)