A new report (Steven B. Giddings and Michelangelo M. Mangano, Astrophysical implications of hypothetical stable TeV-scale black holes, arXiv:0806.3381 ) does a much better job at dealing with the black hole risk than the old “report” Eliezer rightly slammed. It doesn’t rely on Hawking radiation (but has a pretty nice section showing why it is very likely) but instead calculates how well black holes can be captured by planets, white dwarves and neutron stars (based on AFAIK well-understood physics, besides the multidimensional gravity one has to assume in order to get the threat in the first place). The derivation does not assume that Eddington luminosity slows accretion and does a good job at examining how fast black holes can be slowed—it turns out that white dwarves and neutron stars are good at slowing them. This is used to show how dangerously fast planetary accretion rates are incompatible with the observed lifetime of white dwarves and neutron stars.
The best argument for Hawking radiation IMHO is that particle physics is time-reversible, so if there exist particle collisions producing black holes there ought to exist black holes decaying into particles.
A new report (Steven B. Giddings and Michelangelo M. Mangano, Astrophysical implications of hypothetical stable TeV-scale black holes, arXiv:0806.3381 ) does a much better job at dealing with the black hole risk than the old “report” Eliezer rightly slammed. It doesn’t rely on Hawking radiation (but has a pretty nice section showing why it is very likely) but instead calculates how well black holes can be captured by planets, white dwarves and neutron stars (based on AFAIK well-understood physics, besides the multidimensional gravity one has to assume in order to get the threat in the first place). The derivation does not assume that Eddington luminosity slows accretion and does a good job at examining how fast black holes can be slowed—it turns out that white dwarves and neutron stars are good at slowing them. This is used to show how dangerously fast planetary accretion rates are incompatible with the observed lifetime of white dwarves and neutron stars.
The best argument for Hawking radiation IMHO is that particle physics is time-reversible, so if there exist particle collisions producing black holes there ought to exist black holes decaying into particles.