Re:Black holes spin almost at the speed of light
by ncmncm on Saturday August 10, 2019 @08:09PM
(#20665349)
This seemed obvious to me, but not from the "skater" analogy.
Almost every atom entering the event horizon goes in tangentially, because the target is so small, falling from effectively infinite distance, which means it should be going only infinitesimally less than lightspeed at that moment.
The only consumers of kinetic energy would be other particles that happen to enter orbit at a different angle, and collide; and electromagnetic interactions, producing e.g. AGN galactic jets. How much of the kinetic energy gets diverted into those?
I see assertions that the singularity is toroidal, so the actual center of the black hole is not itself singular. Can we posit a fully toroidal event horizon, with a hole through it? Might we expect almost all black holes to be that way?
It's not hard to imagine a black hole spinning one way to get an accretion disk going the opposite way, so I would expect to find the occasional not-spinning-much hole.
Almost every atom entering the event horizon goes in tangentially, because the target is so small, falling from effectively infinite distance, which means it should be going only infinitesimally less than lightspeed at that moment.
The only consumers of kinetic energy would be other particles that happen to enter orbit at a different angle, and collide; and electromagnetic interactions, producing e.g. AGN galactic jets. How much of the kinetic energy gets diverted into those?
I see assertions that the singularity is toroidal, so the actual center of the black hole is not itself singular. Can we posit a fully toroidal event horizon, with a hole through it? Might we expect almost all black holes to be that way?
It's not hard to imagine a black hole spinning one way to get an accretion disk going the opposite way, so I would expect to find the occasional not-spinning-much hole.