Re: Lilliputian Posthumans

From: Eugene Leitl (Eugene.Leitl@lrz.uni-muenchen.de)
Date: Fri Oct 23 1998 - 04:38:44 MDT


John Clark writes:
>
> Difficult yes, impossible no. Hans Moravec figures it would take 10^13
> calculations per second to emulate a human brain. To build one of Drexler's
> nano computers that could perform 10 ^13 calculations per second you'd
> need about half an ounce of matter, mostly of carbon, and about 15 watts
> of energy.
 
A modern high-end PC delivers roughly 10^9 ops peak. Such performance is
distinctly underpowered to run even _one_ neuroanatomically correct neuron
in realtime. Since we have several 10^9 neurons to account for, I do not
see how a factor of 10^4 can make a measurable difference.

Even if we drop the requirements of having to emulate a particular human
brain and settle for an intelligent system instead, I very much doubt that
a 10 k node 21264 Beowulf is capable of intelligent action, however
carefully programmed. (Thinking of several billion transistors/node I
can't help but to notice that a 10 k node Beowulf would seem a
particularly wasteful way of utilizing them, maybe a 10^14 transistor WSI
FPGA++ run by GA could make a fair score on the Turing test).

I don't think that Moravec's notorious underestimates are doing the whole
field of AI a credit.

ciao,
'gene



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