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Related papers: Observational constraints on entropic cosmology

200 papers

A novel fractal structure for the cosmological horizon, inspired by COVID-19 geometry, which results in a modified area entropy, is applied to cosmology in order to serve dark energy. The constraints based on a complete set of observational…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-18 Mariusz P. Dabrowski , Vincenzo Salzano

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

In this paper, after reconstructing the redshift evolution of the Hubble function by adopting Gaussian process techniques, we estimate the best-fit parameters for some flat Friedmann cosmological models based on a Modified Chaplygin Gas…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-28 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

This work considers how exponential corrections to the Bekenstein-Hawking entropy formula affect the thermodynamic behavior of the FLRW cosmological model. These corrections drastically change the form of the Friedman field equations…

High Energy Physics - Theory · Physics 2025-11-25 Rodrigo Rivadeneira-Caro , Joel F. Saavedra , Francisco Tello-Ortiz

This study investigates the evolution of Friedmann-Robertson-Walker (FRW) cosmological models within the $f(Q)$ gravity framework, utilizing a specific $f(Q)$ formulation and a novel Hubble parameter $H(z)$ parameterization to probe the…

General Relativity and Quantum Cosmology · Physics 2025-11-26 Lokesh Kumar Sharma , Suresh Parekh , Anil Kumar Yadav

In view of late-time cosmic acceleration, a dark energy cosmological model is revisited wherein Einstein's cosmological constant is considered as a candidate of dark energy. Exact solution of Einstein field equations (EFEs) is derived in a…

General Relativity and Quantum Cosmology · Physics 2019-11-22 S. K. J. Pacif , Md Salahuddin Khan , L. K. Paikroy , Shalini Singh

A local void in the globally Friedmann-Robertson-Walker (FRW) cosmological model is studied. The inhomogeneity is described using the Lema\^{\i}tre-Tolman-Bondi (LTB) solution with the spherically symmetric matter distribution based on the…

Astrophysics · Physics 2009-10-22 J. W. Moffat , D. C. Tatarski

We discuss the generalized second law (GSL) and the constraints imposed by it for two types of Friedmann universes. The first one is the Friedmann universe with radiation and a positive cosmological constant, and the second one consists of…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-13 Titus K Mathew , Aiswarya R , Vidya K Soman

The question that continues to hinge the interrelation between cosmology and thermodynamics is broadly described as -- what is the form of horizon entropy that links the Friedmann equations for a "$general$" gravity theory with the…

General Relativity and Quantum Cosmology · Physics 2024-01-30 Shin'ichi Nojiri , Sergei D. Odintsov , Tanmoy Paul , Soumitra SenGupta

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

We consider the entropy associated with the large-scale structure of the Universe in the linear regime, where the Universe can be described by a perturbed Friedmann-Lema\^itre spacetime. In particular, we compare two different definitions…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Giovanni Marozzi , Jean-Philippe Uzan , Obinna Umeh , Chris Clarkson

We propose a modification of Einstein-Cartan gravity equations. The modified cosmology departs from the standard model of cosmology for small Hubble parameter. A characteristic Hubble scale h0, which is intrinsically related to cosmological…

General Relativity and Quantum Cosmology · Physics 2015-07-21 Wei Lu

We study the cosmological implications of barotropic fluid satisfying affine equation of state (EoS) in the General relativity and $f(Q)$ gravity framework. We describe the impact of affine EoS on the cosmic evolution in the model and…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Romanshu Garg , G. P. Singh , Ashutosh Singh

Recently, it was argued (Eur. Phys. J. C {\bf73}, 2487 (2013)) that the total entropy of a gravitational system should be related to the volume of system instead of the system surface. Here, we show that this new proposal cannot satisfy the…

General Relativity and Quantum Cosmology · Physics 2016-05-17 H. Moradpour

We present modified cosmological scenarios that arise from the application of the "gravity-thermodynamics" conjecture, using the Barrow entropy instead of the usual Bekenstein-Hawking one. The former is a modification of the black hole…

General Relativity and Quantum Cosmology · Physics 2020-07-22 Emmanuel N. Saridakis

We explore a cosmological model inspired by the modified Kaniadakis entropy and disclose the influences of the modified Friedmann equations on the evolution of the Universe. We find that in modified Kaniadakis cosmology with only…

General Relativity and Quantum Cosmology · Physics 2024-10-01 Mahdi Kord Zangeneh , Ahmad Sheykhi

The recent observations of type Ia supernovae strongly support that the universe is accelerating now and decelerated in the recent past. This may be the evidence of the breakdown of the standard Friemann equation. We consider a general…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yungui Gong , Chang-Kui Duan

We consider a Hubble expansion law modified in the infra-red by distance-dependent terms, and attempt to enforce homogeneity upon it. As a warm-up, we re-derive the basic kinematics of a Friedman Robertson Walker universe without using…

General Relativity and Quantum Cosmology · Physics 2012-04-19 Federico Piazza

Thermodynamics-Gravity conjecture implies that there is a deep connection between the gravitational field equations and the first law of thermodynamics. Therefore, any modification to the entropy expression, directly modifies the field…

General Relativity and Quantum Cosmology · Physics 2023-04-10 Ahmad Sheykhi , Maral Sahebi Hamedan

In the context of Brans-Dicke scalar tensor theory of gravitation, the cosmological Friedmann equation which relates the expansion rate $H$ of the universe to the various fractions of energy density is analyzed rigorously. It is shown that…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Arik , M. C. Calik , M. B. Sheftel