Let's suppose that Hawking Radiation does occur. According to my limited knowledge, as the radius of the event horizon decreases, the emitted Hawking Radiation can (must?) assume ever-smaller wavelengths and ever-higher energies, accelerating the evaporation process, forming a sort of feedback loop. Eventually the black hole disappears in a tremendous release of energy.

Presumably, the violence of these emissions would begin to exert a force on infalling objects away from the black hole (I believe this is known as radiation pressure).

Thus, my question: at some point, does this outward force exceed the black hole's own gravity? At such a point, stationary objects placed near the black hole at some reasonable distance (say, twice the radius of the event horizon) would no longer be attracted to the black hole but instead pushed away. About how large is the black hole at this point? I assume that this is not a long period, and would occur only very close to the point where the black hole vanishes.

To make this concrete, let's suppose that at some point in the future, very advanced ships tow along small black holes and use them as a very efficient way of converting matter into photons. The black hole would need to be sufficiently small so that those aboard the ship would be able to extract a reasonable amount of energy from it via this process; I wonder if this would be an extremely precarious position, since neglecting to feed the black hole for a short amount of time could result in the black hole becoming so luminous it would become difficult to add more material to it, and then rapidly evaporating thereafter.


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