The Fingerprints of Black Holes - Shadows and their Degeneracies
| Autor: | Claudio F. Paganini, Marius A. Oancea, Marc Mars |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Physics
Angular momentum Physics and Astronomy (miscellaneous) 010308 nuclear & particles physics Plane (geometry) Astrophysics::High Energy Astrophysical Phenomena Relative velocity FOS: Physical sciences Charge (physics) Geometry Observer (special relativity) General Relativity and Quantum Cosmology (gr-qc) Mathematical Physics (math-ph) 01 natural sciences Specific relative angular momentum Electric charge General Relativity and Quantum Cosmology Black hole 0103 physical sciences 010303 astronomy & astrophysics Mathematical Physics |
| Zdroj: | Classical and quantum gravity |
| DOI: | 10.48550/arxiv.1710.02402 |
| Popis: | We show that, away from the axis of symmetry, no continuous degeneration exists between the shadows of observers at any point in the exterior region of any Kerr-Newman black hole spacetime of unit mass. Therefore, except possibly for discrete changes, an observer can, by measuring the black holes shadow, determine the angular momentum and the charge of the black hole under observation, as well as the observer's radial position and angle of elevation above the equatorial plane. Furthermore, his/her relative velocity compared to a standard observer can also be measured. On the other hand, the black hole shadow does not allow for a full parameter resolution in the case of a Kerr-Newman-Taub-NUT black hole, as a continuous degeneration relating specific angular momentum, electric charge, NUT charge and elevation angle exists in this case. Comment: 23 pages, 0 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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