On Fri, 19 Dec 1997 Robin Hanson <hanson@econ.Berkeley.EDU> Wrote:
>negentropy (= max sys entropy - actual entropy)
How is this a useful concept? you can't calculate the maximum system entropy
or even prove it's finite because it depends on unanswered questions in
cosmology. For example, put 2 atoms in a box, the larger the box the larger
the entropy of the system, but just how large a box can you make?
>there is no particular advantage to erasing bits at lower
>temperatures.
There is no energy advantage in erasing bits at any temperature, reversible
computing is always more efficient, although the advantage is greater when
things are hot.
>If it were otherwise you could make a perpetual motion machine:
>erase bits (= replace unknown bits with known bits) at low temps and
>then reverse the operation (replace known bits with unknown bits) at
>high temps. By the "costs less energy" intution this cycle would
>create available energy.
I don't understand why a free energy generating system that has access to
both a hot and cold environment is perpetual motion, it looks like a standard
heat engine to me.
John K Clark johnkc@well.com
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