Re: poly: Bekenstein bound and expanding universe

Mitch Porter writes:
>The Bekenstein bound on the number of distinct states possible
>for a quantum system is an increasing function of energy and radius,
>as I recall. ... "proportional to its surface area", ...
>Nonetheless, since space is expanding (on a supragalactic scale,
>at least), shouldn't the Bekenstein bound on your territory
>also be increasing? Without limit?

I don't think so. To reach the limit implied by your surface area
you'd need more mass than you'd have. The Bekenstsein bound is just
given by saying you can't do better than to pull everything into a
black hole.

Robin Hanson
hanson@econ.berkeley.edu http://hanson.berkeley.edu/
RWJF Health Policy Scholar, Sch. of Public Health 510-643-1884
140 Warren Hall, UC Berkeley, CA 94720-7360 FAX: 510-643-8614
Received on Mon Jan 19 21:18:14 1998