Understanding Spinning Black Holes: A Confused Perspective

[Riogho]

Okay, I know there is observational evidence for spinning black holes, so therefore I must be confused about something, and I want you to tell me what.


If you have a star that is spinning, therefore it has orbital angular momentum (mass revolving around a point), then as it is collapsing in a black hole, it shoots out particles that probably take some of that with it, but not all, and because angular momentum is conserved the black hole will spin.

However, it is my understanding that the actually 'massy' part of the black hole is a simple point structure with a large mass and density with (almost?) infinite curvature. But if it is a point, there is no mass to revolve around this point therefore no more orbital angular momentum.

I've probably screwed up already, but my idea is that like an electron (which is a point particle that has angular momentum) instead of having orbital angular momentum it is transformed into spin angular momentum, (where it acts as if it is 'spinning' though it does not) this would seem to explain it away.

Correct? No?

Thanks for the help.

 

[George Jones]

The singularity for a rotating black hole is a ring.

 

[tiny-tim]

you have to believe in the mathematics!

Okay, I know there is observational evidence for spinning black holes

No, I don't think there is. For spinning pulsars etc, yes, but not (yet!) for black holes.

However, it is my understanding that the actually 'massy' part of the black hole is a simple point structure with a large mass and density with (almost?) infinite curvature. But if it is a point, there is no mass to revolve around this point therefore no more orbital angular momentum.

I've probably screwed up already, but my idea is that like an electron (which is a point particle that has angular momentum) instead of having orbital angular momentum it is transformed into spin angular momentum, (where it acts as if it is 'spinning' though it does not) this would seem to explain it away.

Correct? No?

Thanks for the help.

Yup, your comparison with an electron seems as good as any.

A black hole is a "simple point structure" (well, actually it's a ring structure, as George Jones says, but the ring doesn't rotate).

And it's very difficult to accept that point structures can have gravity or angular momentum or charge.

But if you believe they exist at all, you have to believe in the mathematics, and the mathematics says they do!

Awkward, isn't it?

 

[yenchin]

A rotating black hole 'rotates' in the sense that it 'drags spacetime around it'.

 

[DMKerlin]

The ring previously mentioned comes from the relatively large amounts of anti-energies. These energies have been discovered within the laboratory. They, however, are extremely rare in the universe but when the universe's matter is collected by objects such as black holes it also exhibits a higher concentration of these energies which are actually repulsive to each other which helps to provide the force necessary to maintain a hollow core, the inside of the ring, of a black hole. Many physicists speculate that these rings may actually be the gates into other parallel universes with altered (usually considered inverse) physical governing forces.

 

[Wez]

Just a thought, but my view is the black hole mass must spin to exist in the space time fabric in our universe and by spinning creates a vortex we all know, if it didn't it would tear the fabric and drop to the other side of space time as we know it, what it does there is speculation, I have ideas but not dot this discussion, our fabric heals it's self, black holes and it's core mass must rotate to exist in our universe.

 

[Constantin]

For any outside observer, a black hole only has a surface, and that surface probably can rotate.