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Spinning Black Holes in Astrophysical Environments
Pedro G S Fernandes1, Vitor Cardoso2,3
1Universität Heidelberg, Institut für Theoretische Physik, Philosophenweg 12, 69120 Heidelberg, Germany.
Physical Review Letters
|December 5, 2025
Summary
We found that rotating black hole solutions, described by anisotropic fluids, deviate more from the standard Kerr metric as their spin increases. These findings impact astrophysical environments and black hole physics.
Area of Science:
- Astrophysical black hole physics
- General relativity
- Fluid dynamics
Background:
- The Kerr metric describes rotating black holes in vacuum.
- Astrophysical black holes are often surrounded by complex environments, not vacuum.
- Anisotropic fluids offer a more realistic source for black hole metrics.
Purpose of the Study:
- To find new black hole solutions to Einstein's field equations.
- To analyze the physical properties and observational signatures of these black holes.
- To compare these solutions with the standard Kerr metric.
Main Methods:
- Solving Einstein's field equations for stationary, axially symmetric black holes.
- Using an anisotropic fluid as the source.
- Calculating geodesic properties, shadow features, and energy conditions.
Main Results:
- Stationary, axially symmetric black hole solutions were found.
- Deviations from the Kerr metric increase with black hole spin.
- Physical properties and image features were analyzed.
Conclusions:
- Anisotropic fluids lead to black hole solutions that differ from the Kerr metric.
- Spin is a key factor influencing these deviations.
- These findings are relevant for understanding black holes in astrophysical settings.
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