I'm going to focus on one aspect of Robert Shaw comments for the moment.
>
> There isn't room in physics for new stuff on a scale that affects the
> workings of the brain. Penrose appeals to nonlinearities in quantum
> theory connected with gravity but there is no independant evidence
> of such effects. Quantum gravity is even less likely to be relevant.
>
Actually, there might be room in mesoscopic physics. I'm not counting on
this room for my answer, but its still worth noting. Mesoscopic physics is
probably the most likely area for something fundamentally new and usable to
be found in physics. Quantum gravity will be new, but it probably will not
have applications.
> It's not possible in practice but proving it impossible in princple is
> much harder. You need to discover new physics which has a significant
> effect on processes at the energy levels and time scales found in the
brain.
No, all I have to do is show that quantum chaos is involved. Remember,
chemical reactions are inherently quantum. In my discussions with RZ, I did
get the impression that the firing of individual neurons is not always
according to a predetermined pattern. The neurons themselves, of course, are
much larger than the quantum scale. But, the triggering mechanism is often
at a much smaller scale.
> In known physics the movement of the human brain through its infinite
> dimensional phase space can be precisely predicted by using the
Hamiltonian
> operater.
I would like to see that worked out. If it is true, I'd be very surprised.
Think about perfect billiard balls on a perfect table traveling at 10 meters
per second and intereacting (on average) every meter. Quantum chaos is
involved in their position within 1 second.
Dan M.
