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Cited by 240Astrophysical Phenomena and ObservationsBlack Holes and Theoretical PhysicsRelativity and Gravitational Theory

The DOI matches its Crossref record; 7 of the 7 references it cites were found in a registry or an index.

The apparent shape of a rotating charged black hole, closed photon orbits and the bifurcation set A 4

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Vries, A de·2000·Classical and Quantum Gravity
DOI 10.1088/0264-9381/17/1/309
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Abstract

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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Research works printed but not linked: 3

  1. Luminet J P, 1979, Astron. Astrophys., 75, 228
  2. Quien N, 1995, Spektrum Wiss., 5, 56
  3. de Vries A, 1999, Astrophys. Space Sci.

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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
DOI
10.1088/0264-9381/17/1/309
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
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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