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We prove that, in general, the first law of black hole thermodynamics, $\delta Q=T\delta S$, is violated in $f(T)$ gravity. As a result, it is possible that there exists entropy production, which implies that the black hole thermodynamics…

High Energy Physics - Theory · Physics 2015-05-28 Rong-Xin Miao , Miao Li , Yan-Gang Miao

In this paper we obtain the entropy of the Kerr black hole for a number of modified theories of gravity. We show that as long as the deviation from Einstein Hilbert term consists purely of terms involving scalar curvature and Ricci tensor,…

General Relativity and Quantum Cosmology · Physics 2017-05-09 Spyridon Talaganis , Ali Teimouri

We study thermodynamics of black holes in the deformed Ho\v{r}ava-Lifshitz gravity with coupling constant $\lambda$. For $\lambda=1$, the black hole behaves the Reissner-Norstr\"om black hole. Hence, this is different from the Schwarzschild…

High Energy Physics - Theory · Physics 2015-05-13 Yun Soo Myung

We consider near horizon fall-off conditions of stationary black holes in Einstein-Maxwell-Dilaton theory and find conserved charge conjugate to symmetry generator that preserves near horizon fall-off conditions. Subsequently, we find…

High Energy Physics - Theory · Physics 2018-10-17 M. R. Setare , H. Adami

Dilatations by means of a constant factor can be seen in a double way: as a simple change of units length or as a conformal mapping of the starting spacetime into a ``stretched'' one with the same units length. The numerical value of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Stefano Viaggiu

There are several reasons to support the idea that entropy might be associated to gravity itself. In the absence of a quantum theory of gravity, classical estimators for the gravitational entropy have been proposed. Any viable description…

General Relativity and Quantum Cosmology · Physics 2025-04-17 Alan Alejandro Pánuco Liñán , Daniela Pérez , Carlos Luna , Gustavo E. Romero

In general yes, but also not quite. It is known that if the Bekenstein-Hawking entropy is replaced by some kind of generalized entropy, then the Bekenstein bound may be grossly violated. In this work, we show that this undesired violation…

General Relativity and Quantum Cosmology · Physics 2025-10-17 Hengxin Lu , Yen Chin Ong

Thermodynamic Riemannian geometry provides great insights into the microscopic structure of black holes (BHs). One such example is the Ruppeiner geometry which is the metric space comprising the second derivatives of entropy with respect to…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Syed Masood A. S. Bukhari , Behnam Pourhassan , Houcine Aounallah , Li-Gang Wang

In this work we attempt to overcharge extremal and nearly extremal charged black holes in string theory, known as the Garfinkle-Horowitz-Strominger solution. We first show that extremal black holes cannot be overcharged analogous to the…

General Relativity and Quantum Cosmology · Physics 2019-08-02 Koray Düztaş , Mubasher Jamil

This paper investigates thermodynamics, quasi-normal modes, thermal fluctuations and phase transitions of Reissner-Nordstr\"om black hole with the effects of non-linear electrodynamics. We first compute the expressions for Hawking…

General Relativity and Quantum Cosmology · Physics 2022-05-10 M. Sharif , Amjad Khan

Although we have convincing evidence that a black hole bears an entropy proportional to its surface (horizon) area, the ``statistical mechanical'' explanation of this entropy remains unknown. Two basic questions in this connection are: what…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Rafael D. Sorkin

The thermodynamics and weak cosmic censorship conjecture in Reissner-Nordstr$\ddot{o}$m anti-de Sitter black holes are investigated by the scattering of the scalar field. The first law of thermodynamics in the non-extremal…

High Energy Physics - Theory · Physics 2019-10-17 Deyou Chen , Wei Yang , Xiaoxiong Zeng

The entropy of a black hole can differ from a quarter of the area of the horizon because of quantum corrections. The correction is related to the contribution to the Euclidean functional integral from quantum fluctuations but is not simply…

General Relativity and Quantum Cosmology · Physics 2014-11-17 A. Ghosh , P. Mitra

The Bekenstein-Hawking (BH) entropy is expected to be modified by certain correction terms in the quantum loop expansion. As is well known the logarithmic terms in the entropy of black holes appear as a one-loop addition to the classical BH…

High Energy Physics - Theory · Physics 2020-01-29 Sergey N. Solodukhin

According to the second law of thermodynamics, the arrow of time points to an ever increasing entropy of the Universe. However, exactly how the entropy evolves with time and what drives the growth remain largely unknown. Here, for the first…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-09 Xinghai Zhao , Yuexing Li , Qirong Zhu , Derek Fox

As early as 1902, Gibbs pointed out that systems whose partition function diverges, e.g. gravitation, lie outside the validity of the Boltzmann-Gibbs (BG) theory. Consistently, since the pioneering Bekenstein-Hawking results, physically…

Statistical Mechanics · Physics 2013-07-08 Constantino Tsallis , Leonardo J. L. Cirto

We work on the relation between the local thermodynamic instability and the dynamical instability of large black holes in four-dimensional anti-de Sitter space proposed by Gubser and Mitra. We find that all perturbations suppressing the…

High Energy Physics - Theory · Physics 2007-05-23 SangChul Yoon

Using the BSBM varying-alpha theory, with dark matter dominated by magnetic energy, and the spherical collapse model for cosmological structure formation, we have studied the effects of the dark-energy equation of state and the coupling of…

Astrophysics · Physics 2009-11-10 D. F. Mota , J. D. Barrow

In this article, the thermodynamics of regular black holes with a cosmic string passing through it is studied. We will observe that the string has no effect on the temperature as well as the relation between entropy S and horizon area A.

General Relativity and Quantum Cosmology · Physics 2018-09-20 Ceren H. Bayraktar

We apply Wald's formalism to a Lagrangian within generalised Proca gravity that admits a Schwarzschild black hole with a non-trivial vector field. The resulting entropy differs from that of the same black hole in General Relativity by a…

General Relativity and Quantum Cosmology · Physics 2023-11-01 Javier Chagoya , I. Díaz-Saldaña , J. C. López-Domínguez , C. Martínez-Robles
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