From: Wei Dai (weidai@eskimo.com)
Date: Tue Jan 06 1998 - 15:20:24 MST
On Tue, Jan 06, 1998 at 11:34:12AM -0800, Robin Hanson wrote:
>
> Whatever you could do by erasing bits at low temperature you could do by
> erasing bits at high temperature, and using a heat engine to move free
> energy from the low temp source to the high temp source. (Free energy is
> defined as F = E - TS, and so how much you have depends on the temp.)
Ok, I see what you mean, and I agree. I would guess that it might be more
convenient to move information around instead of energy, but you're right
that the same thermodynamic effect can be achieved either way.
Earlier you mentioned that most normal forms of matter has maximum entropy
that is proportional to mass, but a black hole has entropy that is
proportional to the square of its mass. Of course this is what allows
black holes to have such low temperatures and be used as heat sinks. But
what I'm wondering is if there is some non-black-hole arrangement of
matter that has maximum entropy that is proportional to the square of its
mass (and has a reasonable volume). If such a thing exists then we can
perhaps use it as a memory store and never have to erase anything.
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 14:48:24 MST