Does Quantum Theory Explain Consciousness?

astroengine writes "Quantum theory is often seen as the root cause of unrelated, mysterious phenomena. Take consciousness for example. British physicist Roger Penrose recently argued 'that we will need to invoke 'new physics and exotic biological structures': rewriting quantum theory to make sense of consciousness.' But why do this, especially as there is no apparent causal link between quantum mechanics and the conscious mind? There appears to be a very basic logical fallacy here that even the most prominent physicists seem to be making."

Comments

Penrose is a mystic

[Anonymous Coward]

He wants the brain to be non-computable, non-simulatable. In short, he wants it to be magic. He has no real justification for his position.

Re:Consciousness is weird

[bcrowell]

Consciousness is weird. Quantum theory is weird. Therefore quantum theory must explain consciousness.

That's essentially the argument here, and it's pretty easily seen as fallacious.

Well, the slashdot link, and the New Statesman story linked to from it, don't really do justice to Penrose's idea, so it's not surprising that you've gotten the impression that there's absolutely nothing there. Actually there's something to it, and although as a physicist I don't buy it, it's not completely stupid.

The basic idea is that there are various ways to interpret quantum mechanics. The most popular interpretations are the Copenhagen interpretation and the many-worlds interpretation (MWI).

My own take on it is that Copenhagen and MWI are just different words for talking about the theory, so the distinction isn't empirically testable. Copenhagen does a good job of depicting the psychological experience of doing experiments with quantum-mechanical systems, but Copenhagen is illogical because it gives a special role to measurement, which is actually a physical process like any other.

Penrose's idiosyncratic idea is that he takes Copenhagen seriously, so he says that measurement is somehow *different* from other physical processes. That suggests that consciousness is somehow different from other physical processes. He also claims that his idea is at least in principle empirically testable, that we should be able to see this process happen by studying neurons. He thinks there is something special going on in microtubules.

Slashdot's readers would have been a lot better off just reading the WP article on Penrose's theory.

Re:What fallacy?

[Zaphod The 42nd]

I suspect at some point we will come to terms with the fact that what we call "consciousness" is an emergent phenomenon of the brain, and that it is no more free than a glider in Conway's Game of Life.

Bingo.