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Related papers: Gravitational entropies in LTB dust models

200 papers

We extend the thermodynamic derivation of gravity in the Jacobson framework by generalizing the Clausius relation through a nontrivial entropy functional. We show that entropy deformations appear as modifications of the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-14 H. R. Fazlollahi

We present a general formalism for studying generalized Holographic Dark Energy (HDE) models in which we use a dimensionless form of the area-entropy of cosmological horizons. The future event horizon is applied though the formalism can…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-17 Ilim Cimdiker , Mariusz P. Dabrowski , Vincenzo Salzano

The present work explores different evolutionary phases of isotropically homogeneous and flat cosmos filled with dust fluid in non-minimally coupled gravity. We consider different models of this gravity to discuss the presence of symmetry…

General Relativity and Quantum Cosmology · Physics 2024-07-04 Iqra Nawazish , M. Sharif

We undertake a comprehensive and rigorous analytic study of the evolution of radial profiles of covariant scalars in regular Lemaitre-Tolman-Bondi dust models. We consider specifically the phenomenon of "profile inversions" in which an…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Roberto A. Sussman

The main subjects of the PhD dissertation concern cosmological models considered in Palatini f(R) gravity and scalar-tensor theories. We introduce a simple generalization of the LCDM model based on Palatini modified gravity with quadratic…

General Relativity and Quantum Cosmology · Physics 2016-11-01 Aneta Wojnar

Modified theories of gravity encompass a class of $f(R)$-models that seek to elucidate the observed late time accelerated expansion of the universe. In this study, we examine a set of viable $f(R)$ models (Hu-Sawicki: two cases,…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-15 Kumar Ravi , Anirban Chatterjee , Biswajit Jana , Abhijit Bandyopadhyay

Theories with ingredients like the Higgs mechanism, gravitons, and inflaton fields rejuvenate the idea that relativistic kinematics is dynamically emergent. Eternal inflation treats the Hubble constant H as depending on location.…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Sascha Vongehr

We investigate the generation of the baryon asymmetry within the cosmological framework based on a generalized mass-to-horizon entropy. This entropy, recently proposed as a power-law extension of the Bekenstein-Hawking area law, arises from…

General Relativity and Quantum Cosmology · Physics 2025-11-04 Giuseppe Gaetano Luciano , Emmanuel N. Saridakis

Current observations suggest that our Universe is not incompatible with a small positive spatial curvature that can be associated with rest frames having a "closed" standard topology. We examine a toy model generalisation of the…

General Relativity and Quantum Cosmology · Physics 2018-07-09 Sebastián Nájera , Roberto A. Sussman

A general ansatz for gravitational entropy can be provided using the criterion that, any patch of area which acts as a horizon for a suitably defined accelerated observer, must have an entropy proportional to its area. After providing a…

General Relativity and Quantum Cosmology · Physics 2011-05-05 T. Padmanabhan

A recently proposed generalized entropy by Luciano and Saridakis extends the standard Boltzmann-Gibbs and Bekenstein-Hawking framework through a microscopically motivated construction involving two independent entropic exponents. When…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-21 Matías Leizerovich , Susana J. Landau , Giuseppe Gaetano Luciano , Andreas Papatriantafyllou , Emmanuel N. Saridakis

Our Universe has an arrow of time. In accordance with the second law of thermodynamics, entropy has been increasing ever since the Big Bang. The fact that matter is in thermal equilibrium in the very early Universe, as indicated by the…

General Relativity and Quantum Cosmology · Physics 2020-07-30 Daniele Gregoris , Yen Chin Ong , Bin Wang

Entropic cosmology assumes several forms of entropy on the horizon of the universe, where the entropy can be considered to behave as if it were related to the exchange (the transfer) of energy. To discuss this exchangeability, the…

General Relativity and Quantum Cosmology · Physics 2016-02-19 Nobuyoshi Komatsu , Shigeo Kimura

We investigate the parameter distributions of the viable generalized scalar-tensor theory with conventional dust matter after GW170817 in a model-independent way. We numerically construct the models by computing the time evolution of a…

General Relativity and Quantum Cosmology · Physics 2020-10-22 Shun Arai , Purnendu Karmakar , Atsushi Nishizawa

We analyze the thermodynamical consistency of entropic-force cosmological models. Our analysis is based on a generalized entropy scaling with an arbitrary power of the Hubble radius. The Bekenstein-Hawking entropy, proportional to the area,…

General Relativity and Quantum Cosmology · Physics 2022-02-28 D. J. Zamora , C. Tsallis

This study proposes a unified framework comprising two complementary approaches to constrain three functional forms of $f(T,B)$ gravity, namely the linear, quadratic, and general power law models, by jointly utilizing early and late…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-07 Yahia Al-Omar , Majida Nahili , Nidal Chamoun , Marwan Al-Raeei

The thermal history of a large class of running vacuum models in which the effective cosmological term is described by a truncated power series of the Hubble rate, whose dominant term is $\Lambda (H) \propto H^{n+2}$, is discussed in…

General Relativity and Quantum Cosmology · Physics 2016-04-29 J. A. S. Lima , Spyros Basilakos , Joan Solà

In this paper we explore the possibility to find exact solutions for Teleparallel Gravity (TG) of the type of spherically symmetric Lema\^\i tre-Tolman-Bondi (LTB) dust models. We apply to the LTB metric the formalism of Teleparallel…

General Relativity and Quantum Cosmology · Physics 2022-03-28 Sebastián Nájera , Aram Aguilar , Geovanny A. Rave-Franco , Celia Escamilla-Rivera , Roberto A. Sussman

Using a correspondence between the f(T)-gravity with the power-law entropy corrected version of the holographic dark energy model, we reconstruct the holographic f(T)-gravity model with power-law entropy correction. We fit the model…

General Relativity and Quantum Cosmology · Physics 2013-11-06 K. Karami , S. Asadzadeh , A. Abdolmaleki , Z. Safari

In this work, we examine viable models of $f(Q,T)$ gravity theories against observational data with the aim to constrain the parameter space of these models. We have analysed five different models of $f(Q,T)$ gravity and tested them against…

General Relativity and Quantum Cosmology · Physics 2024-08-28 Shreya Banerjee , Aritrya Paul