Recent content by A Puzzlement

If the black hole is already extremal or nearly so, and the ring is orbiting fast enough, the black hole won’t be able to absorb the ring since then the result would be a super-extremal black hole. The only way the ring could be absorbed would be if it lost some of its angular momentum.

A ring-shaped black hole orbiting another black hole? Interesting!

Yeah, that’s why I came up with the idea of the orbiting ring as a kind of loophole. Since the ring isn’t technically part of the black hole, the super-extremality problem is avoided. However, like you mentioned, we need someone to actually find a solution to the equations for this system...

What would spacetime look like near a black hole that was rotating at its extremal speed and had a ring of matter orbiting it at ultra-relativistic speeds (just outside the photon sphere), such that the ring was orbiting in the same direction as the black hole’s rotation? The ring would add to...

Reversible computation is a somewhat well-known topic. (Quantum computers, for instance, must use reversible gates). Apparently, though, quantum measurements can be reversible too. This also means you could recover the original state by “unmeasuring” the system. Imagine being able to “see” a...

Oops, I meant to say mass, not volume. My mistake.

Ordinarily a black hole’s Schwarzschild radius is linearly proportional to its mass. However, wouldn’t there be a deviation from this rule for extremely large black holes? Suppose we assume dark energy is due to a cosmological constant, whose value is the same everywhere (including inside the...

Hi, I’m 28 years old and live in Minnesota. Most of my knowledge about physics is self-taught. (I love knowledge but don’t tend to thrive too well in academic settings for a number of reasons. Kind of like how some people are spiritual but don’t care for organized religion). Anyway, thanks Greg...