[extropy-chat] Dark matter and ET

[The Avantguardian]

--- Alfio Puglisi <puglisi at arcetri.astro.it> wrote:

> On Sat, 16 Jul 2005, The Avantguardian wrote:
> 
> >Well, I am not sure what the the theoretical or
> real
> >limits on Moore's Law might be but it will take a
> long
> >time to catch up to biology. As far as I, as a
> >biologist, am concerned, DNA IS computronium at a
> >staggering information capacity/density of 340
> >exa-bytes (EB = 10^18 bytes) per cubic centimeter.
> >Just add water. :)
> 
> Does this figure only takes into account the DNA
> molecule, or all the
> supporting proteins around as well? The minimum unit
> would be something
> like a small cell, or maybe a nucleus.

No, it is just the figure for B-DNA with its hydration
spine. It assumes it is maximally packed in a volume.
This is of course multiple strands. To have all that
info on a single strand would take somewhat more
volume due to limited tensile strength although DNA is
incredibly flexible. Even in a normal human cell
nucleus with two copies of every chromosome, there is
1.6 gigabytes of info packed into 6.5 X 10^-11 cubic
centimeters, that comes to a density of a paltry 25
exabytes per cubic centimeter. But I wasn't talking
about a cell, I was talking about DNA as a
computational medium in general. Naked DNA in solution
has been used to solve the "traveling salesman
problem". Feel free to google for refs.

Ciaou. :)
 

The Avantguardian 
is 
Stuart LaForge
alt email: stuart"AT"ucla.edu

"The surest sign of intelligent life in the universe is that they haven't attempted to contact us." 
-Bill Watterson


		
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