[ExI] quantum brains

Stathis Papaioannou stathisp at gmail.com
Wed Jan 20 08:35:50 UTC 2010

2010/1/20 The Avantguardian <avantguardian2020 at yahoo.com>:

>> > All and all, Penrose may not be spot on with his mechanism of microtubules and
>> quantum gravity, but the general gist of his argument is compelling. To dismiss
>> the possibility of QM effects in living organisms due to the "warm and wet"
>> mantra is just lazy science.
>> Penrose's application of Godel's theorem to human thinking as a basis
>> for deducing that the brain is not computable has been dismissed as
>> wrong by just about every critic. That's one of the main problems with
>> the quantum brain idea: there is little reason to think that plain
>> ordinary chemistry is not enough, other than a prejudice that because
>> we feel special, our brains must also be special.
> Whoa. I think you are crossing threads here, Stathis. I am not making any assertions about the computability or incomputability of brain function. I think that is a separate, although potentially related, issue from whether the brain uses quantum mechanics to function. I am merely addressing what I percieve as a classical bias to biology and brain function. For the most part QM *is* computable otherwise it would be worthless to physics.. While Godel's theorem is a mathematical theorem and not a physical theory.. I cannot think of an obvious application of Godel's theorem to physics and even most mathematicians can have valid careers by pretending it doesn't exist.

Penrose thinks there is an as yet undiscovered theory of quantum
gravity which is uncomputable and which is an essential part of brain

> With regard to "ordinary chemistry", QM itself is ordinary because it is everywhere. It doesn't just happen when guys in white coats are looking for it. It's just that it blends unnoticed into the intuition-friendly world of classical physics and chemistry most of the time. But consciousness *is* special in that it has yet to be mechanistically described short of the "wire a bunch of neurons together, let them fire off signals at one another, and voila consciousness" explanation. If it was that easy, it would have been replicated already.

We haven't been able to make self-repairing, self-replicating
machines, and nature has been doing it for billions of years. It's
possible that we will be able to upload minds before we can make
artificial organisms. But that doesn't mean that vitalism is correct.

> That being said, there are a lot of parallels between how people and quantum particles behave. For one thing, they both behave probabilistically. One cannot predict a persons actions in response to a stimulus to the degree that one can predict say a falling brick, the oxidation of iron, or other straightfoward physical process. The best one can do is assign probabilities based on the previous history and the statistical analysis of large ensembles of similar people. While economists try to constrain predicted behavior by rationality, people, even rational people, can and do act irrationally under certain conditions.

You could make the same analogy between quantum particles and any
classical chaotic or truly random system.

Stathis Papaioannou

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