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Related papers: Observational constraints on entropic cosmology

200 papers

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Ivan de Martino

We investigate entropic force cosmological models with the possibility of matter creation and energy exchange between the bulk and the horizon of a homogeneous and an isotropic flat Universe. We consider three different kinds of entropy,…

General Relativity and Quantum Cosmology · Physics 2021-07-27 Hussain Gohar , Vincenzo Salzano

Considering Verlinde's entropic gravity proposal, we focus the effects of fermionic $q$ deformation on the Einstein's field equations and Friedmann equations. For this purpose, we represent the thermodynamical properties of the deformed…

General Relativity and Quantum Cosmology · Physics 2021-07-28 Mustafa Senay

Based on Renyi entropy, we study the entropy corrected version of the holographic dark energy (HDE) model in apparent horizon of spatially flat FLRW universe. Applying the generalized entropy leads to the modified version of the Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-29 Tayeb Golanbari , Khaled Saaidi , Parvin Karimi

In the present work, we study for the first time a scale--dependent gravitational theory in a cosmological context in a matter--dominated era. In particular, starting from the Einstein Hilbert action with cosmological constant assuming…

General Relativity and Quantum Cosmology · Physics 2018-07-13 A. Hernández-Arboleda , Á. Rincón , B. Koch , E. Contreras , P. Bargueño

Understanding the evolution of entropy in the universe is a fundamental aspect of cosmology. This paper investigates the evolution of entropy in a spatially flat $K=0$ universe, focusing on the contributions of matter, radiation, and dark…

General Relativity and Quantum Cosmology · Physics 2025-07-16 Tanisha Joshi , S. D Pathak

We consider a cosmology in which a spherically symmetric large scale inhomogeneous enhancement or a void are described by an inhomogeneous metric and Einstein's gravitational equations. For a flat matter dominated universe the inhomogeneous…

Astrophysics · Physics 2008-11-26 J. W. Moffat

Here, we consider new nonadditive entropy of the apparent horizon $S_K=S_{BH}/(1+\gamma S_{BH})$ with $S_{BH}$ being the Bekenstein--Hawking entropy. This is an alternative of the R\'{e}nyi and Tsallis entropies, that allows us, by…

General Physics · Physics 2025-11-18 S. I. Kruglov

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

A modification of the action of the general relativity produces a different pattern for the growth of the cosmic structures below a certain length-scale leaving an imprint on the cosmic microwave background (CMB) anisotropies. We re-examine…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-01 Andrea Marchini , Valentina Salvatelli

The thermodynamics-gravity conjecture reveals that one can derive the gravitational field equations by using the first law of thermodynamics and vice versa. Considering the entropy associated with the horizon in the form of non-extensive…

General Relativity and Quantum Cosmology · Physics 2021-11-04 Mahnaz Asghari , Ahmad Sheykhi

This paper investigates the cosmological implications of the modified gravity framework known as $f(R,\Sigma, T)$ gravity, focusing on its potential to unify and extend current cosmological models. The theory, introduced by Bakry and…

General Relativity and Quantum Cosmology · Physics 2025-03-04 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan

We develop a new approach to building cosmological models, in which small pieces of perturbed Minkowski space are joined together at reflection-symmetric boundaries in order to form a global, dynamical space-time. Each piece of this…

General Relativity and Quantum Cosmology · Physics 2016-04-12 Viraj A. A. Sanghai , Timothy Clifton

Considering a well-motivated $f(R)$ modified-gravity model, in which an exponential function of the curvature is included, in this paper we implement a statistical data analysis to set constraints on the parameters of the model, taking into…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-01 Mario A. Acero , A. Oliveros

In this study, we introduce a novel late-time effective dark energy model characterized by a quadratic equation of state (EoS) and rigorously examine its observational constraints. Initially, we delve into the background dynamics of this…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 Hossein Moshafi , Alireza Talebian , Ebrahim Yusofi , Eleonora Di Valentino

The Hubble Constant measured from the anisotropy in the cosmic microwave background (CMB) is shown to be independent of small changes from the standard model of the redshift dependence of dark energy. Modifications of the Friedmann equation…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jeremy Mould

We consider nonlinear redshift-dependent equation of state parameters as dark energy models in a spatially flat Friedmann-Lema\^itre-Robertson-Walker universe. To depict the expansion history of the universe in such cosmological scenarios,…

General Relativity and Quantum Cosmology · Physics 2018-02-06 Weiqiang Yang , Supriya Pan , Andronikos Paliathanasis

We challenge the widely held belief that the cosmological principle is an obvious consequence of the observed isotropy of the cosmic microwave background radiation, combined with the Copernican principle. We perform a detailed analysis of a…

Astrophysics · Physics 2009-10-31 R. K. Barrett , C. A. Clarkson

The Friedmann equation is derived for a Newtonian universe. Changing mass density to energy density gives exactly the Friedmann equation of general relativity. Accounting for work done by pressure then yields the two Einstein equations that…

Astrophysics · Physics 2015-06-24 Thomas F. Jordan

The recent type Ia supernova data suggest that the universe is accelerating now and decelerated in recent past. This may provide the evidence that the standard Friedmann equation needs to be modified. We analyze in detail a new model in the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Yungui Gong , Xi-Ming Chen