Results 31 to 40 of about 140,146 (178)
Detectable universes inside regular black holes
European Physical Journal C: Particles and Fields, 2022 While spacetime in the vicinity outside astrophysical black holes is believed to be well understood, the event horizon and the interior remain elusive. Here, we discover a degenerate infinite spectrum of novel general relativity solutions with the same ...
Zacharias Roupas
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Astrophysical black holes [PDF]
Formation of the First Black Holes, 2018 In this chapter, we introduce the concept of a black hole (BH) and recount the initial theoretical predictions. We then review the possible types of BHs in nature, from primordial, to stellar-mass, to supermassive BHs.
Pedro R. Capelo
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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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Primordial Black Holes from Conformal Higgs [PDF]
Physics Letters B, 2023 Scale-invariant extensions of the electroweak theory are not only attractive because they can dynamically generate the weak scale, but also due to their role in facilitating supercooled first-order phase transitions. We study the minimal scale-invariant $
Y. Gouttenoire
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Cosmological coupling of nonsingular black holes [PDF]
Journal of Cosmology and Astroparticle Physics, 2023 We show that — in the framework of general relativity (GR) — if black holes (BHs) are singularity-free objects, they couple to the large-scale cosmological dynamics. We find that the leading contribution to the resulting growth of the BH mass (M BH) as a
M. Cadoni +6 more
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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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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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Tidal forces in dirty black hole spacetimes
European Physical Journal C: Particles and Fields, 2022 Black holes can be inserted in very rich astrophysical environments, such as accretion disks. Although isolated black holes are simple objects in general relativity, their accretion disks may significantly enrich the field configurations of their ...
Haroldo C. D. Lima Junior +3 more
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Astrophysical signatures of black holes in generalized Proca theories [PDF]
Physical Review D, 2018 Explaining the late time acceleration is one of the most challenging tasks for theoretical physicists today. Infra-red modification of Einstein's general theory of relativity (GR) is a possible route to model late time acceleration.
Mostafizur Rahman, A. A. Sen
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Electric Currents along Astrophysical Jets
Galaxies, 2017 Astrophysical black holes and their surrounding accretion disks are believed to be threaded by grand design helical magnetic fields. There is strong theoretical evidence that the main driver of their winds and jets is the Lorentz force generated by these
Ioannis Contopoulos
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