3 ms·
The temperature of a black hole decrease as it gets larger. A black hole colder than 2.7K will absorb energy from background radiation faster than it emits Hawk
by OscarCunningham 8y ago
The temperature of a black hole decrease as it gets larger. A black hole colder than 2.7K will absorb energy from background radiation faster than it emits Hawking radiation. So it will get larger and cooler. Any black hole warmer than 2.7K will emit energy faster than it absorbs. This means it will get smaller and hotter, leading it to lose energy at an increasing rate until it has lost all its energy and evaporates.
The cutoff is at around 4.5×10^22 kg (about the mass of the moon). The event horizon at this mass is only 0.13 mm.
- pc86 8y agoI've always wondered, what would happen if we were able to create a black hole of this small a scale and it didn't evaporate? Something with an EH of a fraction of a millimeter.
- OscarCunningham 8y agoIf we created it on earth? It would swallow the earth and destroy us. But to create one we would have to gather a mass greater than the moon onto the earth, so the gravitational effects would probably destroy us before the black hole formed. Black holes aren't as scary as people think. If being next to a black hole of mass M is bad, then being next to a rock of mass M is probably just as bad.