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Related papers: Generalized Second Law for Cosmology

200 papers

We seek here to unify the second law of thermodynamics with the other laws, or at least to put up a law behind the second law of thermodynamics. Assuming no fine tuning, concretely by a random Hamiltonian, we argue just from equations of…

High Energy Physics - Theory · Physics 2008-11-26 Holger B. Nielsen , Masao Ninomiya

The generalized second law of thermodynamics for a system containing a black hole dynamical horizon is proposed in a covariant way. Its validity is also tested in case of adiabatically collapsing thick light shells.

General Relativity and Quantum Cosmology · Physics 2008-11-26 Song He , Hongbao Zhang

We derive the generalized second law (GSL) for arbitrary cuts of Killing horizons from the perspective of crossed-product gravitational algebras, making use of a recent proposal by one of us for the construction of local gravitational…

High Energy Physics - Theory · Physics 2024-08-14 Thomas Faulkner , Antony J. Speranza

The present work shows that the second law of thermodynamics gets naturally satisfied during the entire cosmic evolution of the universe starting from inflation to the late dark energy era, without imposing any exotic condition. This makes…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Sergei D. Odintsov , Tanmoy Paul , Soumitra SenGupta

This study is conducted to examine the validity of generalized second law of thermodynamics (GSLT) in flat FRW for modified teleparallel gravity involving coupling between a scalar field with the torsion scalar $T$ and the boundary term…

General Relativity and Quantum Cosmology · Physics 2017-07-19 M. Zubair , Sebastian Bahamonde , Mubasher Jamil

We investigate the cosmological implications of generalized mass-to-horizon entropy, a two-parameter extension of the standard Bekenstein entropy based on the mass-to-horizon relation. Assuming the entropy balance relation, we derive the…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Smeehan S Shameeem , Priyesh K , Krishna P. B , Titus K Mathew

We discuss the evolution of the universe in the context of the second law of thermodynamics from its early stages to the far future. Cosmological observations suggest that most matter and radiation will be absorbed by the cosmological…

General Relativity and Quantum Cosmology · Physics 2013-04-03 Andrew P. Lundgren , Ruxandra Bondarescu , Mihai Bondarescu

In the framework of Fractional Action Cosmology (FAC), we study the generalized second law of thermodynamics for the Friedmann Universe enclosed by a boundary. We use the four well-known cosmic horizons as boundaries namely, apparent…

General Physics · Physics 2012-02-14 Ujjal Debnath , Mubasher Jamil , Surajit Chattopadhyay

In this work, we have considered the magnetic universe in non-linear electrodynamics. The Einstein's field equations for non-flat FRW model have been considered when the universe is filled with the matter and magnetic field only. We have…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Tanwi Bandyopadhyay , Ujjal Debnath

We investigate the validity of the Generalized Second Law (GSL) of thermodynamics in a $(2+1)$-dimensional holographic cosmological model with a negative cosmological constant. Adopting a horizon thermodynamics framework, we examine two…

General Relativity and Quantum Cosmology · Physics 2025-08-20 Praveen Kumar Dhankar , Aritra Sanyal , Safiqul Islam , Farook Rahaman , Behnam Pourhassan

In this paper, we study thermodynamical properties of the apparent horizon in a universe governed by quasi-topological gravity. Our aim is twofold. First, by using the variational method we derive the general form of Friedmann equation in…

High Energy Physics - Theory · Physics 2015-06-16 M. H. Dehghani , A. Sheykhi , R. Dehghani

The investigation of modifications to the FLRW cosmology resulting from the consideration of a general entropy for the cosmological apparent horizon is the subject of this study. Building upon the work of Nojiri and collaborators in 2022,…

General Relativity and Quantum Cosmology · Physics 2023-07-26 A. Khodam-Mohammadi , M. Monshizadeh

Although the entropy of black holes in any diffeomorphism invariant theory of gravity can be expressed as the Wald entropy, the issue of whether the entropy always obeys the second law of black hole thermodynamics remains open. Since the…

General Relativity and Quantum Cosmology · Physics 2021-09-15 Xin-Yang Wang , Jie Jiang

When a black hole is in an empty space on which there is no matter field except that of the Hawking radiation (Hawking field), then the black hole evaporates and the entropy of the black hole decreases. The generalised second law guarantees…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Hiromi Saida

Late-time cosmic acceleration has motivated the exploration of various extensions of general relativity, among which $f(Q,\mathcal{T})$ gravity, based on the non-metricity scalar $Q$ and the trace of the energy--momentum tensor…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Anirudh Pradhan , A. Husain , M. Zeyauddin , S. H. Shekh

The holographic bound that the entropy (log of number of quantum states) of a system is bounded from above by a quarter of the area of a circumscribing surface measured in Planck areas is widely regarded a desideratum of any fundamental…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jacob D. Bekenstein

Here we are trying to find the conditions for the validity of the generalized second law of thermodynamics (GSLT) assuming the first law of thermodynamics on the event horizon in both cases when the FRW universe is filled with interacting…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Nairwita Mazumder , Subenoy Chakraborty

The second law of thermodynamics is known to hold at small scales also when gravity plays a leading role, as in the case of black holes and self-gravitating radiation spheres. It has been suggested that it should as well at large scales.…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-19 Manuel Gonzalez-Espinoza , Diego Pavón

If simple entropy in the Bekenstein-Hawking area law for a Schwarzschild black hole is replaced with 'negative' quantum conditional entropy, which quantifies quantum entanglement, of positive-energy particles of the black hole relative to…

High Energy Physics - Theory · Physics 2025-04-04 Koji Azuma , Go Kato

Recently a number of papers have claimed that the horizon area - and thus the entropy - of near extremal black holes in anti-de Sitter spacetimes can be reduced by dropping particles into them. In this note we point out that this is a…

General Relativity and Quantum Cosmology · Physics 2019-11-20 Shi-Qian Hu , Yen Chin Ong , Don N. Page
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