[gustavus]

> I mean everything in the universe is in motion and spins…

My understanding is that is a pretty open question as to whether or not blackholes due spin at all, or if they are all uniform apart from mass. Last I heard they do have temperature and electric charge and mass.

Another question is what does the concept of motion even mean for a singularity. How do you define the concept of distance in a non-euclidean space for an object to move through in the first place. What can the idea of movement even mean for an object that has a horizon beyond which it functionally becomes cut off from the rest of the universe.

[roywiggins]

Probably all physical black holes have some spin because they gain it from the matter that falls into it: it's conservation of angular momentum, basically. There are precise mathematical versions of rotating black holes:

https://en.wikipedia.org/wiki/Kerr_metric?wprov=sfla1

[drdeca]

Black holes spin. (I think this is reflected in the data from LIGO about the gravitational waves from mergers?)

This spinning isn’t about the singularity spinning, but the frame dragging around the event horizon.