SV: Capacity of the brain
eugene.leitl at lrz.uni-muenchen.de
Wed Sep 15 15:16:12 EST 1999
Tim Tyler writes:
> : that's why any 'normal' nervous system will always 'kick the butt' of any
> : formerly-'normal' nervous system that has anything shoved in-there.
> But this is hardly right. A coprocessor to perform mathematical
> operations could massively outperform neurons on the same task. Basically
It depends on the complexity. As soon as you need a lot of atomic
operations (=require nontrivial complexity) wetware starts to
outperform you because it does things mostly via massively parallel
You'd need a room filled with most current DSPs burning MW of power to
achieve what the bee does within a cubic mm on a uW budget.
> we can design the guts of such a co-processor relatively easily, while we
> have no idea how to go about building one out of wet neurons in any
> reasonable timescale.
If you don't know how design them, GA-grow them.
> Your point about signal distances does not apper to be relevant - a
> maths co-processor could take up very little space. /Perhaps/ the
Relativistic latency is always relevant at the high end, regardless of
> space would be better occupied with neurons - but no-one knows how to go
> about building a "neuronal" maths co-processor, while a silicon one can
> at least be envisaged today.
If you don't know how to do it it doesn't mean anyone else doesn't.
> Also, silicon substrates are inherently better than brain material at
> performing large numbers of sequential calculations rapidly. If you have
Connectionist architectures are not particular to any substrate. You
can very well go neuronal with buckytube logic.
> a problem that *requires* fast, serial computations, a neural net is
Fortunately the number of problems which must be done in above way is
negligeable. Humanity has a strange bias towards sequential stuff,
this trend will be reversed within the next decades.
> simply not the right sort of architecture to use - but it is practically
> the /only/ type of circuiry you can build from neurons.
Biological neurons != artificial neurons.
> Kurzweil has machines supassing human brain material somewhere around the
> middle of the 21st century. I should think that - according to him - it
> will simply be more efficient use of the available space to scoop out the
> bulky, slow, neurons and replace them with modern nanotech crystalline
> computational hardware ;-)
Sound idea, unfortunately pretty tough to do in vivo.
> : if folks go at it on an evolutionary 'time' scale, will they 'get lucky'?
> : nope, 'cause, during all that 'time', 'normal' nervous systems'll 'just' be
> : getting better... there's a bit of Xeno in-there :-)
> This doesn't necessarily follow either. Normal nervous systems can only
> evolve at the rate of the species that owns them. By contrast simulated
> evolution can go through hundreds of generations in a second on a single
> computer for some tasks.
I don't think anybody actually proposes to do anything with wetware,
but the time gene plumbing can do that it will be made obsolete by nano.
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