[dirkc]

From the link you reference:

> Premise 2: No Quantum Shenanigans

> ...

> the mind arises out of ordinary physics. Some people like Roger Penrose would take issue with this argument, believing that there is extra stuff happening in the brain at a quantum level.

And some other people would take issue with the idea that you can talk about a simple physics that excludes quantum physics.

> But for most of us, this is an easy premise to accept.

I'm out.

[marcosdumay]

It's not excluding quantum physics, it's excluding quantum shenanigans.

You'll certainly need chemistry to model the brain; you'll very likely need solid state physics; everything points towards you needing some very low level molecular dynamics.

What you can't use is high temperature long term coherence. Mostly because quantum physics all but forbids it.

[yorwba]

But of course you can talk about simple physics without invoking quantum physics. What do you think physicists did before? Most everyday phenomena can be approximated very well by classical physics, and modeling the full wave-function for every particle wouldn't even get you any results in a reasonable time.

Since neurons are relatively large and dense, I expect a classical approximation wouldn't show any observable difference in behavior. Unless a deviation is shown, I don't think it is necessary to postulate things like Roger Penrose's quantum-gravity "explanation" of consciousness.

[DiThi]

I read it as "everything can be explained with classical physics alone", the same way we can safely assume the Earth is flat for making a small house. We're not going to complicate math by using the curvature the same way we're not worrying about tunneling, spin, entanglement, etc.

[dirkc]

That is exactly why I'm skeptical. Photosynthesis involves quantum entanglement. I'd be surprised if quantum entanglement doesn't play a role in consciousness.

[haltingthoughts]

Saying that quantum effects are present and saying that the human brain is a quantum computer (or more?) and will get exponential speedup are two very different things.

[DiThi]

We have a pretty good understanding of the individual neuron, and we modeled it with good accuracy. We used a very simplified model of it to build deep learning. The problem is the absurd amount of neurons and interconnections that we would have to run to simulate a human brain.

At some point we may find some phenomena for learning that involves some quantum event, but I doubt we have ever to simulate them at the quantum level.