Bekenstein Bound

From: Jim choate <ravage@bga.com>
> The problem I see with this is that there is no connection between a black holes
> mass and surface area (it doesn't have one). In reference to the 'A' in the    
> above, is it the event horizon? A funny thing about black holes is that as the
> mass increases the event horizon gets larger not smaller (ie gravitational
> contraction). 

Actually black holes do have a defined surface area, which is basically, as
you suggest, the area of the event horizon.  And of course this is larger
for more massive black holes, as you say.

I believe the Bekenstein bound is based on reasoning that suggests that
if the state density of a region exceeds that bound, it will essentially
collapse into a black hole and be inaccessible to the rest of the universe.
The surface area in that context can be the conventionally defined area.

To bring this back to crypto a bit, the point of this discussion was that
there can be only a finite amount of processing done in finite time by
a finite-sized machine, even when QM is taken into consideration.  Note,
though, that this result appears to require bringing in quantum gravitation,
a very poorly understood theory at present.

Hal

First off, Black holes are singularities or points and have no volumes.

Second, the 'surface' of the event horizon is a fractal and is therefore
better represented by a volume.

Third, Black holes are not de-coupled from the rest of the universe, they 
emit 'Hawkings Radiation' which eventually leads to the evaporatio of every
black hole, the bigger the faster.

State shifts, such as a electron or the collapse of a Hamiltonian in a 2
slip experiment take zero time. The issue of time is irrelevant.

Fifth, volume is not an issue because several accepted theories imply a 
'many worlds' type of reality. Some of these theories even allow a certain       
amount of information to leak between them. This occurs because when the 
Hamiltonian is constructed some states prevent or exclude other states and the
state space turns out to be smaller than at first apparent.

Sixth, everyone (incl. me initialy) was discussing QED in exclusion. This is 
completely incorrect. You must include QCD and it is a complete unknown at this
point. When QED succeded because of Feynmann the tools were applied to the 
Quantuam Chromodynamics of Quarks and it has not solved any problems.

I did a little scrounging around last nite in my library and came up with w
books which discuss aspects of this without burying it in math.

Mind Children by Hans Moravec (has a discussion on this exact topic)

Quantum Physics: Illusion or Reality? by Alastair Rae

Take care...