Comment by ithkuil
I'm confused.
Hawking temperature is inversely proportional to the mass. I assume most black holes except the very small ones would thus have a hawking temperature lower than the CMB.
Does that mean that effectively no black holes will ever evaporate not even a tiny bit well until the future time when the CMB will be so red shifted that black holes will start to have net radiation?
Wikipedia suggests that this is the case [0]:
"However, since the universe contains the cosmic microwave background radiation, in order for the black hole to dissipate, the black hole must have a temperature greater than that of the present-day blackbody radiation of the universe of 2.7 K. A study suggests that M must be less than 0.8% of the mass of the Earth – approximately the mass of the Moon."
I'm not sure where the discrepancy between the mass of the Moon vs. an asteroid comes from, though.
[0] https://en.wikipedia.org/wiki/Hawking_radiation#Black_hole_e...