Talk:Gleason's theorem

Bohm's theory
I like this article very much, but I would suggest adding one sentence. Currently, the article says:

"The theorem is often taken to rule out the possibility of hidden variables in quantum mechanics."

If you say this, I think that you need to add a caveat. Gleason's theorem doesn't apply to Bohm's theory, which is the only popular hidden variable theory nowadays. Gleason's theorem assumes that you begin by describing a particle by a state in Hilbert space, but Bohm doesn't do that. (For him, a particle has a definite position at all times.) This is a really big loophole, because other hidden-variable approaches could just dispense with Hilbert space altogether.

Personally, I don't really like Bohm's theory, but it does provide a nice counterexample to most "general" statements about hidden-variable theories (as evidenced here)! Sthinks (talk) 07:39, 9 December 2007 (UTC)


 * I agree with this comment. I was quite surprised not to see a mention of Bohm's "pilot wave" model https://en.wikipedia.org/wiki/Pilot_wave_theory. "Bohmian Mechanics" seems perfectly sound, though many would consider its non-locality a flaw. Bohmian Mechanics is based on refactoring the Schrodinger equation, so in a sense offers no new predictions. It's a kind of isomorphism to conventional QM, only with a deterministic, hidden variable interpretation. Wouldn't it therefor be allowed by Gleason's Theorem? 24.5.52.167 (talk) 16:20, 26 July 2022 (UTC)