[extropy-chat] Limits of Physics question

[Robert J. Bradbury]

Within the last couple of months I saw a notice for a paper
documenting some new limits of physics arguments on computation.
The paper seemed to extend work by Anders and Seth Lloyd regarding
how far computing might go.  It seemed to suggest a hard limit
of about 800 years for Moore's Law.

However my best efforts to get Google and/or other search engines
to offer the reference up seem be producing no results.  I had
thought it might have been in Science or Nature, but now I'm leaning
towards one of the more obscure physics journals.

If anyone encounters this paper please send me a reference.

Thanks,
Robert