Friday, August 01, 2008

Conway and Kochen vs. Determinism

John Conway and Simon Kochen are out with a paper called "The Strong Free Will Theorem" (HT), updating and "strengthening" their earlier paper (discussed here). Recall that the theorem begins with axioms which, while idealized, flow from accepted aspects of quantum theory and relativity and then concludes that if humans are assumed to be free in setting up experiments, then particles have the same kind of freedom in selecting among experimental outcomes. The theorem also serves as another argument toward ruling out hidden-variable interpretations of QM.

This paper presents a "stronger" version of the theorem, by showing it still works if one of the axioms is loosened, but otherwise the thrust is unchanged. In keeping with the earlier paper, though, the authors add to the formal argument some provocative philosophical comments, which I enjoy. Here's how the paper concludes:

"Although...determinism may formally be shown to be consistent, there is no longer any evidence that supports it, in view of the fact that classical physics has been superceded by quantum mechanics, a non-deterministic theory. The import of the free will theorem is that it is not only current quantum theory, but the world itself that is non-deterministic, so that no future theory can return us to a clockwork universe."


TechTonics said...

I'm not so sure that QM has replaced General Relativity as a universal theory. I'm under the impression that QM and GM aren't reconciled because of quantum gravity which I think mostly has to do with time, or human perception of time.
I noticed that you mentioned panpsychism in another post. Have you thought about whether this free will theorem bestowing elementary particles with free will also implies the other roots/mechanisms of mind and consciousness, thus panpsychism?

Steve said...

Hi and thanks for your comment.

You're right that we don't have a quantum gravity theory yet and there are several possible routes to such a theory. I am "betting" that quantum physics will survive in the new theory while GR will prove to be an effective, low-energy approximation, but not a fundamental part of the new theory. I have a few posts on this kind of research with the quantum gravity label.

I do think the idea of some kind of freedom at the micro-level goes together with the idea of panpsychism. The idea would be that the elementary consituent of the world is an inherently experiential quantum event which is an actualization (or "choice") of one of a set of possibilities.