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Related papers: Some comments on the universal constants

200 papers

The current observational and experimental bounds on time variation of the constants of Nature are briefly reviewed.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Takeshi Chiba

Black holes are famous for their universal behavior. New thermodynamic relations have been found recently for the product of gravitational entropies over all the horizons of a given stationary black hole. This product has been found to be…

High Energy Physics - Theory · Physics 2015-06-15 Alejandra Castro , Nima Dehmami , Gaston Giribet , David Kastor

We review recent progress in our understanding of the physics of black holes. In particular, we discuss the ideas from string theory that explain the entropy of black holes from a counting of microstates of the hole, and the related…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sumit R. Das , Samir D. Mathur

This letter contains a brief discussion on the leading-order canonical correction to the Bekenstein-Hawking (black hole) entropy. In particular, we address some recent criticism directed at an earlier commentary.

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. J. M. Medved

We give a method in which a quantum of mass equal to twice the Planck mass arises naturally. Then using Bose-Einstein statistics we derive an expression for the black hole entropy which physically tends to the Bekenstein-Hawking formula.

General Relativity and Quantum Cosmology · Physics 2009-10-31 B. Ram

The definition of entropy obtained for stationary black holes is extended in this paper to the case of non-stationary black holes. Entropy is defined as a macroscopical thermodynamical quantity which satisfies the first principle of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. Allemandi , L. Fatibene , M. Francaviglia

Two types of self-gravitating particle solutions found in several theories with non-Abelian fields are smoothly connected by a family of non-trivial black holes. There exists a maximum point of the black hole entropy, where the stability of…

General Relativity and Quantum Cosmology · Physics 2009-10-22 K. Maeda , T. Tachizawa , T. Torii , T. Maki

Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-Hawking (black hole) entropy, which relates the entropy to the cross-sectional area of the black hole horizon. Using generalized…

General Relativity and Quantum Cosmology · Physics 2015-03-30 Abdel Nasser Tawfik , Eiman Abou El Dahab

We review some recent advances in black hole thermodynamics, including statistical mechanical origins of black hole entropy and its leading order corrections, from the viewpoints of various quantum gravity theories. We then examine the…

High Energy Physics - Theory · Physics 2008-11-26 Saurya Das

Several comments are given to previous proofs of the generalised second law of thermodynamics: black hole entropy plus ordinary matter entropy never decreases for a thermally closed system. Arguments in favour of its truism are given in the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. -T. Sung

The universe today, with structure such as stars, galaxies and black holes, seems to have evolved from a very homogeneous initial state. From this it appears as if the entropy of the universe is decreasing, in violation of the second law of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Oystein Rudjord , Oyvind Gron

We study the validity of Bekenstein's entropy bound for a charged black hole in the context of nonlinear electrodynamics. Bekenstein's inequalities are commonly understood as universal relations between the entropy, the charge, the…

General Relativity and Quantum Cosmology · Physics 2021-04-30 F. T. Falciano , M. L. Peñafiel , J. C. Fabris

The entropy for two-dimensional black holes is obtained through the entropy function with the condition that the geometry approaches an $AdS_2$ spacetime in the near horizon limit. It is shown that the entropy is universal and proportional…

High Energy Physics - Theory · Physics 2010-10-27 Seungjoon Hyun , Wontae Kim , John J. Oh , Edwin J. Son

Recently, there has been much attention devoted to resolving the quantum corrections to the Bekenstein-Hawking entropy of the black hole. In particular, many researchers have expressed a vested interest in the coefficient of the logarithmic…

General Relativity and Quantum Cosmology · Physics 2009-03-19 Zhao Hai-Xia , Li Huai-Fan , Hu Shuang-Qi , Zhao Ren

Without pretending to any rigour, we find a general expression of the electrostatic self-energy in static black holes with spherical symmetry. We determine the entropy bound of a charged object by assuming the existence of thermodynamics…

General Relativity and Quantum Cosmology · Physics 2009-10-31 B. Linet

We argue that the entropy of a black hole is due to the entanglement of matter fields and gravitons across the horizon. While the entanglement entropy of the vacuum is divergent because of UV correlations, we show that low-energy…

General Relativity and Quantum Cosmology · Physics 2013-01-08 Eugenio Bianchi

The issue of a possible damping of the entropy periodicity for large black holes in Loop Quantum Gravity is highly debated. Using a combinatorics/analysis approach, we give strong arguments in favor of this damping, at least for…

General Relativity and Quantum Cosmology · Physics 2011-11-09 Xiangyu Cao , Aurelien Barrau

The Black Hole Uncertainty Principle correspondence proposes a connection between the Uncertainty Principle on microscopic scales and black holes on macroscopic scales. This is manifested in a unified expression for the Compton wavelength…

General Relativity and Quantum Cosmology · Physics 2014-02-07 B. J. Carr

The comparison of geometrical properties of black holes with classical thermodynamic variables reveals surprising parallels between the laws of black hole mechanics and the laws of thermodynamics. Since Hawking's discovery that black holes…

History and Philosophy of Physics · Physics 2019-03-18 Carina E. A. Prunkl , Christopher G. Timpson

We provide some up-to-date discussions related to cosmological event horizon and entropy of our universe, then introduce an intriguing idea that there may be a universal finite upper bound for entropy accessible to an observer in consistent…

High Energy Physics - Theory · Physics 2026-05-27 Min-xin Huang