There is a point where a black hole will decay faster than it can absorb mass. What the point is I couldn't even guess, but it's probably some impossibly huge number they don't even have a word for.
There is a point where a black hole will decay faster than it can absorb mass. What the point is I couldn't even guess, but it's probably some impossibly huge number they don't even have a word for.
they do. I's called "jacob's number." it's a number between 0 and infinity that would require *all the matter in the universe to write down... and for some reason it ends with 7.
There is a point where a black hole will decay faster than it can absorb mass. What the point is I couldn't even guess, but it's probably some impossibly huge number they don't even have a word for.
The way Hawking radiation works is that a black hole has an "effective temperature". Just like with ordinary matter, energy will flow from a hot object to cold surroundings, with the rate being determined by the magnitude of the temperature difference.
Unfortunately, the effective temperature of a black hole is inversely related to its mass. As a BH acceretes matter (gains mass), its temperature decreases and it radiates less, not more. Given current understanding of stellar evolution and core-collapse supernova, the smallest possible mass for a newly-formed, stellar mass black hole is about five times the mass of our sun. Such a black hole has an effective temperature of 1.234 x 10^-8 K, or 12 billionths of a degree above absolute zero, which is really fucking cold. SMBH are even colder, by many orders of magnitude.
The only way for a black hole to be emitting enough Hawking radiation for it to be plausibly detectable is for it be so small we can't imagine how it could form, except to say that a Big Bang did it.
The way Hawking radiation works is that a black hole has an "effective temperature". Just like with ordinary matter, energy will flow from a hot object to cold surroundings, with the rate being determined by the magnitude of the temperature difference.
Unfortunately, the effective temperature of a black hole is inversely related to its mass. A BH gaining mass radiates less, not more. The point where the radiation emitted exceeds what the BH can "eat" is for very small BHs, and we don't know how BHs that small could form except to say "a Big Bang did it".
Based on that it seems reasonable that, if a black hole were somehow find itself in the extra-galactic void, it would eventually evaporate.
I just thought of something, what happens if two black holes collide. Would they merge seamlessly, or would the “larger” one tear mass off of the “smaller” one?
I just thought of something, what happens if two black holes collide. Would they merge seamlessly, or would the “larger” one tear mass off of the “smaller” one?
A black hole collision normally ends in a merger. The result can hardly be called seamless; it is extremely energetic, burning through dozens of solar masses worth of energy in seconds. These create a curvature of space-time that radiates outward at the speed of light, a gravitational wave. The collision as seen from the outside is fairly simple. There is a steady inspiral increasing in frequency as the two holes get closer together. The amplitude of the gravitational wave jumps up as the merger begins, and settles rapidly as they become a single hole.
There is a point where a black hole will decay faster than it can absorb mass. What the point is I couldn't even guess, but it's probably some impossibly huge number they don't even have a word for.
That’s actually a good point. At one point we observed a Black Hole, but it wasn’t very dangerous because it was far enough away to not be a viable threat to us.
Black Holes come in different shapes and sizes, however, and some are more dangerous than others.
