This was partially inspired by the event horizon post, I’ve heard of Hawkings radiation recently but don’t understand it, any help?
In: Physics
At quantum scales, the vacuum of deep space is not actually a vacuum, but a quantum “foam” of virtual particle and antiparticle pairs which continually wink into existence and then immediately annihilate. Ordinarily, this results in no net mass change and no net energy change for the universe at large; however, immediately adjacent to the event horizon of a black hole things behave a bit differently. A photon and its corresponding antiphoton can come into existence in the quantum vacuum, but then instead of immediately annihilating, one happens to cross the event horizon and be lost to the black hole while the other escapes to infinity because it is now unpaired. Technically, the radiation is not being emitted by the black hole (which cannot emit anything by definition), but rather by the space just beyond the horizon, but the effect is the same as if the black hole itself were radiating.
A consequence of this Hawking radiation is that it provides a mechanism for the black hole to lose energy, since the absorbed photon must necessarily carry the same absolute quantity of energy of the emitted photon, only negative as it is the conjugate. This allows for black holes to evaporate, as the negative energy robs it of momentum over time, maintaining the energy balance of the universe.
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