Discussion Overview
The discussion centers around the properties of black holes, specifically their electrical charge and spin, and how these characteristics can exist despite the singularity being described as a point of zero volume. Participants explore the implications of these properties on the nature of black holes and the underlying physics.
Discussion Character
- Exploratory
- Technical explanation
- Debate/contested
- Conceptual clarification
Main Points Raised
- Some participants question how a black hole can possess spin or angular momentum if it is formed from a mass that collapses into a point of zero volume, suggesting that the singularity may still be spinning or that spacetime is being dragged around it.
- Others propose that the charge and angular momentum of the original star must be retained in the black hole, raising the question of where these properties would go otherwise.
- One participant notes that elementary particles, which are also modeled as point-like, can carry intrinsic charge and angular momentum, drawing a parallel to black holes.
- It is mentioned that Kerr and Newman black holes do not contract into points but rather to circles, which still have zero volume due to their lack of thickness.
- A later reply asserts that the laws of conservation (angular momentum, charge, mass-energy) apply during the formation of a black hole, indicating that a black hole retains the angular momentum and charge of the star, unless these were lost during collapse.
- Another participant challenges the claim that black holes have "zero" volume, suggesting that this assertion is incorrect.
Areas of Agreement / Disagreement
Participants express differing views on the nature of black holes regarding their volume, spin, and charge. There is no consensus on the implications of these properties or the accuracy of the claims made about them.
Contextual Notes
Some statements rely on specific definitions of volume and charge, and the discussion includes unresolved questions about the nature of singularities and the behavior of spacetime around them.