English
Related papers

Related papers: Brans-Dicke Cosmology: Thermodynamic viability

200 papers

We investigate the laws of thermodynamics in an accelerating universe driven by dark energy with a time-dependent equation of state. In the case we consider that the physically relevant part of the Universe is that envelopped by the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Bin Wang , Yungui Gong , Elcio Abdalla

The thermodynamical aspects of the conformal time scale factor duality (SFD) of cosmological models within Einstein Gravity are investigated. We derive the SFD transformations of the thermodynamical quantities describing the thermal…

High Energy Physics - Theory · Physics 2017-03-01 G. M. Sotkov , A. L. Alves Lima , U. Camara da Silva

We study the evolution of a flat Friedmann-Robertson- Walker Universe, filled with a bulk viscous cosmological fluid, in the presence of variable gravitational and cosmological constants. The dimensional analysis of the model suggest a…

General Relativity and Quantum Cosmology · Physics 2009-09-25 J. A. Belinchon , T. Harko , M. K. Mak

By using the scattering of a scalar field, we discuss the thermodynamics and overcharging problem in a 4D Gauss-Bonnet AdS black hole in both the normal phase space and extended phase space. In the normal phase space, where the cosmological…

General Relativity and Quantum Cosmology · Physics 2020-11-03 Benrong Mu , Jing Liang , Xiaobo Guo

We investigate the validity of the generalized second law of thermodynamics on the $(n-1)$-dimensional brane embedded in the $(n+1)$-dimensional bulk. We examine the evolution of the apparent horizon entropy extracted through relation…

High Energy Physics - Theory · Physics 2010-05-12 Ahmad Sheykhi , Bin Wang

A study of a complete cosmological model based on an asymmetric scalar doublet represented by the classical and phantom scalar Higgs fields is carried out. At the same time, the assumption about the nonnegativity of the expansion rate of…

General Relativity and Quantum Cosmology · Physics 2021-04-05 Yu. G. Ignat'ev , I. A. Kokh

We apply the gravity-thermodynamics conjecture, namely the first law of thermodynamics on the Universe horizon, but using the generalized Kaniadakis entropy instead of the standard Bekenstein-Hawking one. The former is a one-parameter…

General Relativity and Quantum Cosmology · Physics 2021-12-07 Andreas Lymperis , Spyros Basilakos , Emmanuel N. Saridakis

We consider a Brans-Dicke cosmology in five-dimensional space-time. Neglecting the quadratic and the mixed Brans-Dicke terms in the Einstein equation, we derive a modified wave equation of the Brans-Dicke field. We show that, at high energy…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. Errahmani , T. Ouali

A bouncing scenario of a flat homogeneous and isotropic universe is explored by using the reconstruction technique for the power-law parametrization of the Hubble parameter in a modified gravity theory with higher-order curvature and trace…

General Relativity and Quantum Cosmology · Physics 2023-04-03 J. K. Singh , Harshna Balhara , Kazuharu Bamba , J. Jena

We investigate the cosmological consequences of a brane-world theory which incorporates time variations in the gravitational coupling G and the cosmological term Lambda. We analyze in detail the model where (dG/dt)/G ~ H and Lambda ~ H^2,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Ponce de Leon

The whole article deals with the analysis of the cosmic model of Ruban's space-time in the context of a bulk viscosity impact in the form of Ricci dark energy within the framework Brans-Dicke theory (Brans and Dicke, Phys. Rev. 124, 925…

General Relativity and Quantum Cosmology · Physics 2023-11-03 M. Vijayasanthi , T. Chinnappalanaidu , S. Srivani Madhu

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

We perform a symmetry analysis of modified Brans-Dicke cosmological equations and present exact solutions. We discuss how the solutions may help to build models of cosmology where, for the early universe, the expansion is linear and the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Metin Arik , Mikhail B. Sheftel

In this work we have studied the possibility of obtaining cosmic acceleration in Brans-Dicke theory with varying or constant $\omega$ (Brans- Dicke parameter) and with or without self-interacting potential, the background fluid being…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Writambhara Chakraborty , Ujjal Debnath

The five dimensional Brans-Dicke theory naturally provides two scalar fields by the Killing reduction mechanism. These two scalar fields could account for the accelerated expansion of the universe. We test this model and constrain its…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Li-e Qiang , Yan Gong , Yongge Ma , Xuelei Chen

We investigate the unified first law and the generalized second law in a modified holographic dark energy model. The thermodynamical analysis on the apparent horizon can work and the corresponding entropy formula is extracted from the…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Hui Li , Yi Zhang

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

In this paper we have considered the holographic dark energy and studied it's cosmology and thermodynamics. We have analysed the generalized second law (GSL) of thermodynamics in a flat universe consists of interacting dark energy and dark…

General Relativity and Quantum Cosmology · Physics 2014-02-03 Praseetha P. , Titus K. Mathew

Extensions of the gravitational framework of Brans-Dicke (BD) are studied by considering two different scenarios: i) `BD-$\Lambda$CDM', in which a rigid cosmological constant, $\Lambda$, is included, thus constituting a BD version of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-27 Javier de Cruz Perez , Joan Sola Peracaula

By integration of generalized BSBM and Brans-Dicke cosmological models, in this article, we investigate the theoretical framework of fine structure constant variation and current cosmic acceleration. We first develop a mathematical…

General Relativity and Quantum Cosmology · Physics 2015-06-11 H. Farajollahi , A. Salehi
‹ Prev 1 8 9 10 Next ›