Results 11 to 20 of about 56,013 (217)
“Black Star” or Astrophysical Black Hole? [PDF]
AIP Conference Proceedings, 2008 Recently wide publicity has been given to a claim by T. Vachaspati that "black holes do not exist", that the objects known as black holes in astrophysics should rather be called "black stars" and they not only do not have event horizons but actually can be the source of spectacular gamma ray bursts.
K. Petrovay +3 more
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Are astrophysical “black” holes leaky?
International Journal of Modern Physics D, 2022 We continue a study by Adler and Ramazanoǧlu (AR) of “black” holes as modified by a scale invariant dark energy action. For the spherically symmetric Schwarzschild-like case, AR found that there is no event horizon; hence spacetime is not divided by the “black” hole into causally disconnected regions.
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Astrophysical Appearance of Primordial Black Holes
Astronomy Reports, 2023 14 pages, 3 figures, Paper presented at the Fifth Zeldovich meeting, an international conference in honor of Ya. B. Zeldovich held in Yerevan, Armenia on June 12--16, 2023. Submitted to Astronomy Reports by the recommendation of the special editors: R. Ruffini, N. Sahakyan and G.
Postnov, Konstantin +2 more
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Can accretion disk properties distinguish gravastars from black holes? [PDF]
, 2009 Gravastars, hypothetic astrophysical objects, consisting of a dark energy condensate surrounded by a strongly correlated thin shell of anisotropic matter, have been proposed as an alternative to the standard black hole picture of general relativity ...
Bhattacharyya S +31 more
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Constraints on relic magnetic black holes
Journal of High Energy Physics, 2022 We present current direct and astrophysical limits on the cosmological abundance of black holes with extremal magnetic charge. Such black holes do not Hawking radiate, allowing those normally too light to survive to the present to do so.
Melissa D. Diamond, David E. Kaplan
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, 2015 Published in 2015 as Chapter 1 of 'General Relativity: The most beautiful of theories: Applications and trends after 100 years', Edited by Carlo Rovelli (pub. De Gruyter)
Fabian, Andrew C., Lasenby, Anthony N.
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Black Hole Astrophysics in AdS Braneworlds [PDF]
Journal of High Energy Physics, 2003 We consider astrophysics of large black holes localized on the brane in the infinite Randall-Sundrum model. Using their description in terms of a conformal field theory (CFT) coupled to gravity, deduced in Ref. [1], we show that they undergo a period of rapid decay via Hawking radiation of CFT modes.
Emparan, Roberto +2 more
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Photon-Sphere Modes in Curved Optical Microcavities: A Black-Hole Analogue Laser. [PDF]
Adv Sci (Weinh)An optical analogue of a Schwarzschild black hole is realized using curved microcavities that preserve light‐like geodesics. A new family of laser modes confined around the photon sphere is identified alongside conventional whispering‐gallery modes. Analytical theory, numerical simulations, and experiments reveal curvature‐induced confinement, enabling
Xu C +9 more
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Gravitational lensing by a Horndeski black hole
European Physical Journal C: Particles and Fields, 2017 In this article we study gravitational lensing by non-rotating and asymptotically flat black holes in Horndeski theory. By adopting the strong deflection limit, we calculate the deflection angle, from which we obtain the positions and the magnifications ...
Javier Badía, Ernesto F. Eiroa
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Extremal bifurcations of rotating AdS4 black holes
Journal of High Energy Physics, 2021 The Weak Gravity Conjecture arises from the assertion that all extremal black holes, even those which are “classical” in the sense of being very massive, must decay by quantum-mechanical emission of particles or smaller black holes.
Brett McInnes
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