[extropy-chat] Dark matter and ET

[Damien Sullivan]

On Tue, Jul 19, 2005 at 11:22:06AM +0200, Eugen Leitl wrote:
> On Tue, Jul 19, 2005 at 01:38:19AM -0700, Damien Sullivan wrote:
> 
> > Maybe, but saying that DNA itself is computronium is I think a bit much.
> > It's
> 
> Computronium is a molecular crystal made from computing cells, optimized 
> for doing computation. DNA is nothing like computronium. Dry cold DNA is a

Is a rod-logic computer a crystal?  I've always defined computronium as matter
optimized for computation; exactly how will depend on the tech available.  And
as Wikipedia on computronium points out, on the goals: speed, storage, energy
efficiency, mass efficiency, cost...

> No, in terms of energy efficiency and functionality concentration a human or
> an insect brain is very far removed from what we can currently do. 

This seems in contradiction of the facts I possess, such as our difficulty in
matching insect functionality, with devices which weigh more and consume more
power.

> > But I figure a brain has 1e6 to 1e8 times the raw computing power of a
> > desktop CPU (or more accurately, would take that many CPUs to be
> > emulated), while
> 
> We don't know what the equivalent is. There are no comparable benchmarks.

We know the brain has 1e11 units, 1e14 synapses, and update frequencies of up
to 1000 Hz.  1e17 flops.  I can see needing 'only' 1e14 in practice, if much
of the brain is idle at any moment and 100 Hz is more like the real update
speed.  And about 1e14 bytes of RAM.

> CPUs alone are useless. You need to look at the total mass of a Blue Rack,
> included the machine room and the air conditioning versus a ~75 kg human.
> Here the efficiency becomes particularly abysmal.

I don't see it.  100 W for the total human system, with advanced face
recognition, speech recognition, speech production, planning, robotics, Go
playing (potential) and partial protection against hostile replicating goo, to
put a few things in CS terms.  Well, for the naked human; if you start
counting First World lifestyle it's 1e4 Watts.  But brains being practical
computronium doesn't have to mean using human beings; it can mean grown arrays
of neurons, or cyborged animals.

-xx- Damien X-)