Better link: https://arxiv.org/abs/2106.15181
The results are fairly obvious: CMB and Hawking radiation provide almost zero power output, while an accretion disk and relativistic jets can provide a lot of power.
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The results are fairly obvious: CMB and Hawking radiation provide almost zero power output, while an accretion disk and relativistic jets can provide a lot of power.
In theory you can get an arbitrary amount of power from Hawking radiation if you have a lot of very small black holes instead of just one big one. I feel like the stability of the negative-feedback control systems for their orbits might be important here, especially if they're orbiting something you care about like your home planet.
The central theoretical problem is that taking Hawking seriously, the stuff inside stays inside, but inside goes away. What happens to the stuff? There are more theoretical answers to that written down than there are actual theorists, and presently no astronomical or laboratory observations which let us throw practically any of them away.
(Also of course, inside might not go away after all -- not at all or not completely -- with large numbers of explanations of how that might work, and nothing concretely observed that lets us discount such possibilities in favour of total evaporation.)