How can black holes have electrical charge, and spin?

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SUMMARY

The discussion centers on the properties of black holes, specifically their electrical charge and spin. It establishes that Kerr and Newman black holes do not collapse into singular points but rather into circles with zero volume. The conservation laws for angular momentum and charge remain intact during the formation of black holes, meaning that if a star possesses angular momentum or charge prior to collapse, the resulting black hole retains these properties. The assertion that black holes have "zero" volume is deemed incorrect.

PREREQUISITES
  • Understanding of Kerr and Newman black holes
  • Familiarity with the concept of singularities in general relativity
  • Knowledge of angular momentum and charge conservation laws
  • Basic grasp of black hole formation processes
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  • Study the implications of singularities in general relativity
  • Explore the conservation laws related to black hole formation
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Astronomers, physicists, and students of theoretical physics interested in black hole properties, general relativity, and the conservation of angular momentum and charge in astrophysical processes.

Lamdbaenergy
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If the star's mass supposedly collapses into a single point, and it ends up having "said" zero volume, then how can people say that the hole has a specific spin or that it can have an angular momentum?

Does it mean that the singularity is somehow still spinning, or maybe the spacetime around it is just being dragged for some reason?
This subject has been confusing me quite a bit whenever I think about it.
 
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Where would the charge and angular momentum of the star go otherwise?

On a related issue: Elementary particles are also modeled as point like, yet can carry both intrinsic charge and angular momentum.
 
Lamdbaenergy said:
If the star's mass supposedly collapses into a single point, and it ends up having "said" zero volume, then how can people say that the hole has a specific spin or that it can have an angular momentum?

Does it mean that the singularity is somehow still spinning, or maybe the spacetime around it is just being dragged for some reason?
This subject has been confusing me quite a bit whenever I think about it.

Sometimes the BH's gravity field is referred to as a 'fossil' field-

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_gravity.html
 
Turns out Kerr and Newman black holes do NOT contract into points. They contract to circles... which still have zero volume, because zero thickness throughout their nonzero circumference.
Reissner black holes are point charges, just like Schwarzschild black holes.
 
In short: the laws of conservation (angular momentum, charge, mass-energy, etc.) still work during the process of creation of a black hole. So if a star had some angular momentum/charge before it collapsed, the resulting black hole will also have some (assuming the angular momentum/charge was not radiated away during the collapse).

Also, the claim that black holes have "zero" volume is simply incorrect.
 

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