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Overspinning a black hole with a test body
Ted Jacobson1, Thomas P Sotiriou
1Center for Fundamental Physics, University of Maryland, College Park, Maryland 20742-4111, USA.
Physical Review Letters
|November 13, 2009
Summary
Researchers demonstrate that black holes below maximal spin can be overspun by test bodies. This requires the test body to have orbital but not spin angular momentum, excluding radiative effects.
Area of Science:
- Astrophysics
- General Relativity
- Black Hole Physics
Background:
- Maximally spinning black holes are theoretically stable against overspinning by test bodies.
- The behavior of sub-maximally spinning black holes under such conditions is less understood.
Purpose of the Study:
- To investigate whether a black hole with below-maximal spin can be overspun.
- To determine the conditions under which overspinning is possible.
Main Methods:
- Theoretical analysis of black hole dynamics.
- Consideration of test body properties, including size, internal structure, and angular momentum.
Main Results:
- Overspinning of a sub-maximally spinning black hole is achievable.
- The test body must possess orbital angular momentum but not spin angular momentum.
- Specific size and internal structure requirements for the test body are identified.
Conclusions:
- Black hole overspinning is possible under specific initial conditions and test body properties.
- Radiative and self-force effects are neglected and may influence the outcome.
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