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The apparent shape of a rotating charged black hole, closed photon orbits and the bifurcation set A 4
Open accessAbstract
The apparent shapes of various Kerr-Newman spacetimes are plotted. For this purpose the geometry of closed photon orbits is studied, forming a subset of the bifurcation set A 4 , well known in elementary catastrophe theory. One additional result is that the cosmic censorship hypothesis guarantees that the spacetime casts a shadow, whereas naked ring singularities enable the visibility of the `anti-world' of negative radii r through its interior. Moreover, the optical restrictions to the observability of the shadow of an astronomical black hole are inferred.
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“Models of optically thin spherical accretion fl ows around SMBHs generically predict that they will appear to distant observers as bright rings of emission surrounding a darker central ' shadow '”
From First Sagittarius A* Event Horizon Telescope Results. IV. Variability, Morphology, and Black Hole Mass (2022) · cites this paper as de Vries 2000
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Citations
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Metadata
- Authors
- Vries, A. D.
- Affiliations
- Ruhr University Bochum (DE)
- Corresponding author
- Vries, A de
- ORCID
- Vries, A de
- Venue
- Classical and Quantum Gravity
- Publisher
- IOP Publishing
- Published
- 1999-12-13
- Volume
- 17
- Issue
- 1
- Pages
- 123-144
- ISSN
- 0264-9381 (ISSN-L)
- 1361-6382
- OpenAlex
- W2164202970
- Cited by
- 240
- References
- 7
- Citations by year
- 2026: 11 · 2025: 24 · 2024: 19 · 2023: 20 · 2022: 26 · 2021: 26 · 2020: 33 · 2019: 10 · 2018: 17 · 2017: 4 · 2016: 8 · 2015: 8 · 2014: 6 · 2013: 7 · 2012: 3
- FWCI
- 0.54
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- Classical and Quantum Gravity (publishedVersion)
- Topics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Astrophysical Phenomena and Observations
- Physical Sciences › Physics and Astronomy › Nuclear and High Energy Physics › Black Holes and Theoretical Physics
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Relativity and Gravitational Theory
- Keywords
- Kerr-Newman black hole, charged rotating black holes, catastrophe theory, cosmic censorship, black hole shadow, optical geometry
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