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Related papers: Hawking temperature and the emergent cosmic space

200 papers

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

We examine the second law of thermodynamics in the context of horizon cosmology, in particular, whether the change of total entropy (i.e. the sum of the entropy for the apparent horizon and the entropy for the matter fields) proves to be…

General Relativity and Quantum Cosmology · Physics 2024-04-09 Sergei D. Odintsov , Tanmoy Paul , Soumitra SenGupta

In this article we have used the recently introduced redefined Hawking temperature on the event horizon and investigated whether the generalised second law of thermodynamics (GSLT) and thermodynamic equilibrium holds for both the event and…

General Relativity and Quantum Cosmology · Physics 2016-05-04 Subhajit Saha , Subenoy Chakraborty

The present work deals with a cosmological model having particle creation mechanism in the framework of irreversible thermodynamics. In the second order non-equilibrium thermodynamical prescription, the particle creation rate is treated as…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Subenoy Chakraborty , Supriya Pan , Subhajit Saha

In this paper, we investigate the evolution of the early universe within an emergent fractional cosmological framework. The underlying formulation is conceptually rooted in generalized measure constructions, closely related to fractal…

General Relativity and Quantum Cosmology · Physics 2026-04-16 S. M. M. Rasouli

The black hole singularity problem was proposed by Hawking and Penrose, and regular black holes serve as an important class of models to address this issue. However, the study of regular black hole thermodynamics has long faced a…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Qi-Quan Li , Yu Zhang , Hoernisa Iminniyaz

We disclose the thermodynamical properties of the apparent horizon in a nonsingular universe. We take into account the zero-point length correction to the gravitational potential and derive the modified entropy expression that includes…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Ahmad Sheykhi , Leila Liravi , Kimet Jusufi

In a recent article we have introduced Friedmann thermodynamics, where certain geometric parameters in Friedmann models are treated like their thermodynamic counterparts (temperature, entropy, Gibbs potential etc.). This model has the…

General Relativity and Quantum Cosmology · Physics 2008-04-02 Selcuk S. Bayin

The Friedmann equations of general relativity can be derived from the first law of thermodynamics when the entropy of the apparent horizon of a spatially isotropic universe is given by the Bekenstein-Hawking entropy. We point out that if…

General Relativity and Quantum Cosmology · Physics 2009-11-19 James E. Lidsey

Recently, Barrow accounts for the quantum gravitational effects to the black hole surface. Thus the conventional area-entropy relation has modified, $S=(A/A_{0})^{1+\Delta/2},$ with an exponent $\Delta$, ranges $0\le\Delta\le1$, quantifies…

General Relativity and Quantum Cosmology · Physics 2023-02-06 Nandhida Krishnan. P , Titus K Mathew

The cosmological principle, promoting the view that the universe is homogeneous and isotropic, is embodied within the mathematical structure of the Robertson-Walker (RW) metric. The equations derived from an application of this metric to…

Astrophysics · Physics 2014-11-18 Fulvio Melia

Over the last decades, observations with increasing quality have revolutionized our understanding of the general properties of the Universe. Questions posed for millenia by mankind about the origin, evolution and structure of the cosmos…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 Ricardo T. Génova-Santos

This article presents a simple model that reproduces key concepts of modern cosmology within the framework of special relativity, at a level that is suitable for an undergraduate or high school setting. The model includes cosmic expansion…

General Relativity and Quantum Cosmology · Physics 2019-01-14 Markus Pössel

Homogeneous and isotropic, nonsingular, bouncing world models are designed to evade the initial singularity at the beginning of the cosmic expansion. Here, we study the thermodynamics of the subset of these models governed by general…

General Relativity and Quantum Cosmology · Physics 2016-03-09 Pedro C. Ferreira , Diego Pavon

By analytically continuing the time variable in a black hole background, and requiring unitary evolution, it is found that quantum mechanical states at the horizon develop a thermal factor under suitable identification of the physical time.…

High Energy Physics - Theory · Physics 2007-05-23 Tze-Dan Chung

In the standard cosmological theory one uses the Einstein concepts of space and time as were originally introduced for the special theory of relativity and the general relativity theory. According to this approach all physical quantities…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

We develop a comprehensive cosmological framework based on the principle that our universe originated as a three-dimensional spatial configuration governed purely by energy functionals, with time emerging dynamically through quantum loop…

General Physics · Physics 2026-01-13 Farrukh A. Chishtie

In this second part of our series of two papers, where spacetime is modelled by a graph, where Planck size quantum black holes lie on the vertices, we consider the thermodynamics of spacetime. We formulate an equation which tells in which…

General Relativity and Quantum Cosmology · Physics 2009-10-21 J. Makela

In the present article, we study the Hawking effect and the bounds on greybody factor in a spacetime with radial deformation. This deformation is expected to carry the imprint of a non-Einsteinian theory of gravity, but shares some of the…

General Relativity and Quantum Cosmology · Physics 2023-01-11 Subhajit Barman , Sajal Mukherjee

We use a method recently introduced in Barcel\'o et al (2011 Phys. Rev. D 83 41501), to analyse Hawking radiation in a Schwarzschild black hole as perceived by different observers in the system. The method is based on the introduction of an…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Luis C. Barbado , Carlos Barceló , Luis J. Garay