X-Message-Number: 14998 Date: Thu, 23 Nov 2000 13:58:56 +0100 From: Henri Kluytmans <> Subject: Re: Clancy, brief comment Pat Clancy wrote : >But physical/quantum reality happens at infinite >precision, and the infinite precision "calculations" of reality happen instantly - <snip> >you cannot just calculate the positions and momenta of particles as they <snip> >would not run in real time, i.e. that you could in theory simulate sequentially >those things that were instantaneous in reality, <snip> Of course, a discrete system cannot imitate an analog system (or a quantum mechanical system) with exact precision. However the question is : "Is exact accuracy required?" First of all, it doesn't seem likely that details at the quantum mechanical are essential for the functioning of the mind. (And that's what is the issue here.) And it seems that most neuro-scientists tend to agree. If you think so, can you give me the scientific motivation as to why ? (By the way, even an analog system cannot imitate an other analog system exactly in practice! Because therefore you would need to measure it with exact precision, which is fundamentally impossible according to physics.) ==== However exact precision is not required... Any analog system is in practice being perturbed all the time. Indeed a single fluctuation in some quantum state(s) can determine the direction/result of our thought processes. But you don't even need quantum mechanics for that, a single particle or photon of background radiation could also do that. Or the fluctuation of thermal energy of a single particle in your mind. However our thought processes do not seem to be very chaotic... The question is : "What is essential for the functioning of the mind?" ==== Lets make this clear by an example : A computer is also a system made of particles governed by quantum mechanics. Continuously there are changes and fluctuations in the quantum states of those particles. Are the exact states important for the functioning of the of the computer? ..NO What is important for the functioning however, is the statistical behavior of larger numbers of particles due to their quantum mechanical states. Otherwise, for example, a transistor circuit wouldn't work. Analogously, the exact thermal states of the particles are not relevant. However the average thermal states of larger systems of particles is. The high level logic functioning of a computer does not depend on the exact states of the single particles. But still a single particle or thermal fluctuation could determine the outcome of a calculation in that computer. (And that last one, is more likely to happen when your computer gets hotter.) I assume you agree with all this? (... for a computer) ==== So, because the functioning of our mind does not seem to display a chaotic behavior (for most people :> ) it seems that it's functioning is based on mechanisms that operate at a higher level, and that the fluctuations in the lower level mechanisms are statistically evened out. Also randomly destroying a certain amount of single neurons does not seem to disturb the functioning of our mind. The same appears to be true for artificial neural networks. This all seems to imply that we do not need to make an imitation with infinite precision, to imitate the functioning of the mind. ** With "functioning of the mind" I mean : "High level functions, like intelligent behavior, feelings, selfconsciousness." Cheers, >Hkl Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=14998