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Related papers: Hawking temperature and the emergent cosmic space

200 papers

Scalar radiation, represented by a massless scalar field in a Robertson-Walker metric, is taken into account. By using a weak non minimum vacuum definition, the radiation temperature as a time dependent function is obtained. When the…

High Energy Physics - Theory · Physics 2007-05-23 Carlos E. Laciana

The possibility of an emergent universe solution to Einstein's field equations allowing for an irreversible creation of matter at the expense of the gravitational field is shown. With the universe being chosen as spatially flat FRW…

General Relativity and Quantum Cosmology · Physics 2016-09-27 Sunandan Gangopadhyay , Anirban Saha , S. Mukherjee

We consider dynamical black hole formation from a collapsing fluid described by a symmetric and flat FRW metric. Using the Hamilton-Jacobi method the local Hawking temperature for the formed trapping/apparent horizon is calculated. The…

General Relativity and Quantum Cosmology · Physics 2016-01-04 Rudolf Baier , Stefan Stricker

We show that the first law of the black hole thermodynamics can lead to the tunneling probability through the quantum horizon by calculating the change of entropy with the quantum gravity correction and the change of surface gravity is…

High Energy Physics - Theory · Physics 2009-01-06 Baocheng Zhang , Qing-yu Cai , Ming-sheng Zhan

A local Hawking temperature is derived for any future outer trapping horizon in spherical symmetry, using a Hamilton-Jacobi variant of the Parikh-Wilczek tunneling method. It is given by a dynamical surface gravity as defined geometrically.…

General Relativity and Quantum Cosmology · Physics 2009-02-11 S. A. Hayward , R. Di Criscienzo , M. Nadalini , L. Vanzo , S. Zerbini

Cosmological equations were recently derived by Padmanabhan from the expansion of cosmic space due to the difference between the degrees of freedom on the surface and in the bulk in a region of space. In this study, a modified R\'{e}nyi…

General Relativity and Quantum Cosmology · Physics 2017-04-14 Nobuyoshi Komatsu

This paper investigates the phenomenon of emergence of spatial curvature. This phenomenon is absent in the Standard Cosmological Model, which has a flat and fixed spatial curvature (small perturbations are considered in the Standard…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-01 Krzysztof Bolejko

We present a novel cosmological framework that unifies matter creation dynamics with thermodynamic principles. Starting with a single-component fluid characterized by a constant equation of state parameter, $\omega$, we introduce a…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-27 Víctor H. Cárdenas , Samuel Lepe

The Kepler problem is considered in a space with the Friedmann--Lemaitre--Robertson--Walker metrics of the expanding universe. The covariant differential of the Friedmann coordinates (X=a(t)x) is considered as a possible mechanism of the…

Astrophysics · Physics 2009-11-07 A. Gusev , P. Flin , V. Pervushin , S. Vinitsky , A. Zorin

Recently, we have generalized the Bekenstein-Hawking entropy formula for black holes embedded in expanding Friedmann universes. In this letter, we begin the study of this new formula to obtain the first law of thermodynamics for dynamical…

High Energy Physics - Theory · Physics 2015-08-11 Stefano Viaggiu

Most of the calculations done to obtain the value of the cosmological constant use methods of quantum gravity, a theory that has not been established as yet, and a variety of results are usually obtained. The numerical value of the…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

Based on the cosmological principle only, the method of describing the evolution of the Universe, called cosmography, is in fact a kinematics of cosmological expansion. The effectiveness of cosmography lies in the fact that it allows, based…

General Relativity and Quantum Cosmology · Physics 2018-12-07 Yu. L. Bolotin , V. A. Cherkaskiy , O. Yu. Ivashtenko , M. I. Konchatnyi , L. G. Zazunov

A celebrated result by Jacobson is the derivation of Einstein's equations from Unruh's temperature, the Bekenstein-Hawking entropy and the Clausius relation. This has been repeatedly taken as evidence for an interpretation of Einstein's…

General Relativity and Quantum Cosmology · Physics 2014-08-20 Goffredo Chirco , Hal M. Haggard , Aldo Riello , Carlo Rovelli

We formulate the basic framework of thermodynamical entropic force cosmology which allows variation of the gravitational constant $G$ and the speed of light $c$. Three different approaches to the formulation of the field equations are…

High Energy Physics - Theory · Physics 2016-03-10 Mariusz P. Dabrowski , H. Gohar , Vincenzo Salzano

In this paper, we propose a model in which an additional pressure due to the effects of the entropic force is added to the ideal fluid. Furthermore, we obtain the dynamic equation in the FRW universe which contains the quantum gravitational…

High Energy Physics - Theory · Physics 2016-03-08 Fei-Quan Tu , Yi-Xin Chen

We rephrase the derivation of black hole radiation so as to take into account, at the level of transition amplitudes, the change of the geometry induced by the emission process. This enlarged description reveals that the dynamical variables…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. Massar , R. Parentani

A very interesting new proposal on the origin of the cosmic expansion was recently suggested by Padmanabhan [arXiv:1206.4916]. He argued that the difference between the surface degrees of freedom and the bulk degrees of freedom in a region…

General Relativity and Quantum Cosmology · Physics 2013-09-24 A. Sheykhi , M. H. Dehghani , S. E. Hosseini

We propose a novel cosmological scenario with the space-time emerging from a pure initial de Sitter stage and subsequently evolving into the radiation, matter and dark energy dominated epochs, thereby avoiding the initial singularity and…

General Relativity and Quantum Cosmology · Physics 2015-06-11 J. A. S. Lima , S. Basilakos , Joan Sola

Spacetimes with horizons show a resemblance to thermodynamic systems and it is possible to associate the notions of temperature and entropy with them. Several aspects of this connection are reviewed in a manner appropriate for broad…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Padmanabhan

In this thesis, the implications of a new cosmological model are studied, which has features similar to that of decaying vacuum cosmologies. Decaying vacuum (or cosmological constant \Lambda) models are the results of attempts to resolve…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Moncy V. John