Article
Physics, Mathematical
M. Dehghani, M. R. Setare
Summary: The explicit form of the field equations for Einstein-dilaton gravity with scalar-coupled exponential nonlinear electrodynamics has been obtained. Exact black hole solutions were found in an energy-dependent spherically symmetric geometry, with the scalar field equation solutions obtained by combining two Liouville potentials. Three types of exponentially charged dilatonic black holes were introduced and their thermodynamic properties studied in relation to rainbow functions. The impacts of rainbow functions on the conserved and thermodynamic quantities of the new black hole solutions were explored, showing the validity of the first law of black hole thermodynamics and examining quantum gravitational effects on thermodynamic phase transitions.
INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
(2021)
Article
Astronomy & Astrophysics
Changjun Gao
Summary: This article discusses the construction of exact black hole solutions with multiple horizons in Einstein-nonlinear electrodynamic theories, deriving the explicit expression of a nonlinear electrodynamic Lagrangian for 3-horizon black holes. Furthermore, investigations are made on the horizons, null and timelike geodesics, Love numbers, and thermodynamics of the three-horizon black holes.
Article
Astronomy & Astrophysics
Daniele Malafarina, Bobir Toshmatov
Summary: This article discusses the correspondence between black holes in nonlinear electrodynamics and gravitational collapse of homogeneous dust with semiclassical corrections, and explores the insights that can be gained from considering this correspondence.
Article
Physics, Multidisciplinary
Pedro Canate, Santiago Esteban Perez Bergliaffa
Summary: We propose a method to create regular black hole spacetimes that satisfy the solutions of General Relativity with nonlinear electrodynamics (NLED), based on a metric derived from the mass function of a singular black hole geometry. The singular metric may not be a vacuum or electro-vacuum solution of General Relativity.
Article
Astronomy & Astrophysics
A. Bokulic, I Smolic, T. Juric
Summary: This study rederives the first law of black hole mechanics in the presence of nonlinear electrodynamics fields and discusses the validity of energy conditions, complementary proofs of the zeroth law of black hole electrodynamics, and aspects of the recently generalized Smarr formula, including its (non-)linearity and relation to the first law.
Article
Astronomy & Astrophysics
Fatemeh Naeimipour, Behrouz Mirza, Soudabe Nasirimoghadam
Summary: In this study, two types of Yang-Mills-dilaton black hole solutions were obtained in both Lifshitz and hyperscaling violation spacetimes, with differences in thermodynamic properties and stability. It was found that for negative values of the hyperscaling violation parameter, the thermal stability of the solutions exhibited some special cases.
Article
Physics, Particles & Fields
Georgios K. Karananas, Alex Kehagias, John Taskas
Summary: A novel four-dimensional black hole model is proposed, with expected growth of entanglement entropy before Page's time, but later modified significantly by emergent islands, leading to saturation at a finite value. The study reveals that the entanglement entropy changes along the RG flow with respect to the two-dimensional worldsheet length scale.
JOURNAL OF HIGH ENERGY PHYSICS
(2021)
Article
Physics, Particles & Fields
Deyou Chen, Yucheng He, Jun Tao
Summary: In this paper, topological numbers for five-, six- and seven-dimensional anti-de Sitter black holes in the ghost-free massive gravity are studied. It is found that charged black holes have the same topological number. The topological numbers for uncharged black holes are either 0 or 1, with specific values determined by the parameters of the black holes. This work demonstrates the important role of the parameters of the ghost-free massive gravity in the topological classes of black holes.
EUROPEAN PHYSICAL JOURNAL C
(2023)
Article
Physics, Nuclear
Jiuyang Tang, Yunqi Liu, Wei-Liang Qian, Ruihong Yue
Summary: In this study, the effect of nonlinear electrodynamics on the shadows of charged, slowly rotating black holes with a cosmological constant is investigated. The trajectory of a photon, as a perturbation of the nonlinear electrodynamic field, is determined by an effective metric rather than the null geodesic of the background black hole spacetime. By analyzing the propagation of a discontinuity of the electromagnetic waveform, the effective metric can be derived and used to evaluate the image and shadow of the black hole using backward ray-tracing technique. The study explores the properties of black hole shadows in different scenarios of nonlinear electrodynamics and their dependence on other metric parameters.
Article
Astronomy & Astrophysics
Fabrizio Corelli, Marina de Amicis, Taishi Ikeda, Paolo Pani
Summary: Einstein-dilaton-Gauss-Bonnet gravity is a gravity theory that provides a natural framework to study the high-curvature regime beyond general relativity. Black holes in this theory exhibit nonperturbative effects due to dilatonic coupling, resulting in a minimum mass solution that separates stable and unstable branches. This study focuses on the nonlinear collapse of scalar hair onto black holes near the minimum mass, investigating the transition from unstable to stable branch and assessing the latter's stability. Additionally, the collapse of a phantom field onto the black hole reveals a high-curvature elliptic region when the black hole mass decreases past the critical value, suggesting a violation of weak cosmic censorship or the emergence of horizonless remnants.
Article
Physics, Multidisciplinary
James Lucietti
Summary: The study shows that in a generalized Majumdar-Papapetrou class of solutions to higher-dimensional Einstein-Maxwell theory, the only asymptotically flat spacetimes with a suitably regular event horizon are the standard multi-black holes. The proof involves a careful analysis of near-horizon geometry and an extension of the positive mass theorem to Riemannian manifolds with conical singularities, completing the classification of asymptotically flat, static, extreme black hole solutions in this theory.
ANNALES HENRI POINCARE
(2021)
Article
Physics, Particles & Fields
Hyewon Han, Bogeun Gwak
Summary: We studied the effects of metric fluctuations on the geometry of higher-dimensional black holes and extended the four-dimensional model to higher dimensions to account for quantum vacuum fluctuations. Using a perturbation method for small fluctuation amplitudes, we obtained the null geodesic equation for radially outgoing rays up to second order in the fluctuations. The fluctuation of the event horizon and the thermodynamic variables defined at the horizon also have dimension-dependent correction terms up to second order. A general solution for rays propagating near the horizon in a fluctuating geometry was derived, and in the large D limit, a compact form solution was found.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Ming-Hui Yu, Xian-Hui Ge
Summary: The Fabbri-Russo model is a generalized model of a two-dimensional dilaton gravity theory, where Page curves and entanglement islands are investigated. The emergence of islands in any black hole causes the deceleration of the entanglement entropy of radiation after the Page time, satisfying the principle of unitarity. The shape of Page curves is independent of the parameter n in the leading order, indicating universality in generalized two-dimensional models. The island is proposed as a better solution than firewalls for the quantum entanglement-monogamy problem.
Article
Physics, Multidisciplinary
Ibrahim Gullu, S. Habib Mazharimousavi
Summary: In this study, electric and magnetic black hole solutions are discovered by combining a nonlinear electrodynamics model with cosmological Einstein gravity. The solutions display properties of Reissner-Nordstrom black hole in different limits and are expressed through different equations. The thermodynamic aspects and stability of the magnetic black hole solution are analyzed through modified Smarr's formula and heat capacity calculations.
Article
Physics, Nuclear
Jie-Xiong Mo, Shan-Quan Lan
Summary: This study investigates the dynamic phase transition of charged dilaton black holes, revealing that with increasing parameter, the horizon radius difference between large and small dilaton black holes increases, the system requires more time to achieve a stationary distribution, and the dilaton field slows down the dynamic phase transition process between large and small black holes.