Energy, over a very long period of time. Remember that mass and energy are equivalent.
Hawking temperature is inversely proportional to black hole size, so the bigger the hole the "colder" it is. The largest black holes will start evaporating very slowly once the CMB drops below their temperature.
A tiny micro black hole, if one were created, would evaporate almost instantly converting 100% of its mass into energy, basically a bomb. E.g. a 1kg micro black hole smaller than an electron would have a yield similar to a small hydrogen bomb, most of which would be released as ultra high energy gamma rays.
Black holes are awesome. In some ways they are the most extreme things in the universe, the extreme-est of extreme physics.
The mass-energy density required to create them is so far beyond anything humanly possible that trying to do so with, for example, hydrogen bombs would be not much better than trying to do it by squeezing really hard with your hand. It requires things like the first few milliseconds after the Big Bang (if primordial black holes exist) or collapsing massive stars. To give a sense of this density: a black hole with the mass of the Earth would be about the size of a marble (Schwartzchild radius). Inside of course there's either a true singularity or -- if certain theories of quantum gravity are correct -- a region of some kind of maximum-theoretical-density matter. (Some theories predict that true singularities don't exist.)
If somehow someday it were possible to create or control them, it would be possible to access energies far beyond fusion or even antimatter-driven reactions... think perfect direct mass-energy conversion with near 100% efficiency.
kolanos|1 year ago
api|1 year ago
Hawking temperature is inversely proportional to black hole size, so the bigger the hole the "colder" it is. The largest black holes will start evaporating very slowly once the CMB drops below their temperature.
A tiny micro black hole, if one were created, would evaporate almost instantly converting 100% of its mass into energy, basically a bomb. E.g. a 1kg micro black hole smaller than an electron would have a yield similar to a small hydrogen bomb, most of which would be released as ultra high energy gamma rays.
Black holes are awesome. In some ways they are the most extreme things in the universe, the extreme-est of extreme physics.
The mass-energy density required to create them is so far beyond anything humanly possible that trying to do so with, for example, hydrogen bombs would be not much better than trying to do it by squeezing really hard with your hand. It requires things like the first few milliseconds after the Big Bang (if primordial black holes exist) or collapsing massive stars. To give a sense of this density: a black hole with the mass of the Earth would be about the size of a marble (Schwartzchild radius). Inside of course there's either a true singularity or -- if certain theories of quantum gravity are correct -- a region of some kind of maximum-theoretical-density matter. (Some theories predict that true singularities don't exist.)
If somehow someday it were possible to create or control them, it would be possible to access energies far beyond fusion or even antimatter-driven reactions... think perfect direct mass-energy conversion with near 100% efficiency.
superposeur|1 year ago