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Related papers: Modified cosmology through Barrow entropy

200 papers

The standard big bang cosmology has been greatly successful in explaining many observational aspects of the real universe. However, two particular diffficulties faced by it are the so-called ``horizon'' and ``flatness'' problems. By…

General Physics · Physics 2007-05-23 Abhas Mitra

We study FLRW cosmology, taking into account quantum gravitational corrections in the formalism of the exact renormalization group flow of the effective action for gravity. We calculate the quantum corrected scale factor, energy density,…

General Relativity and Quantum Cosmology · Physics 2022-10-26 Rituparna Mandal , Sunandan Gangopadhyay , Amitabha Lahiri

In this work, we propose a new dark energy model by applying the Barrow entropy and the holographic principle, with a time scale as IR cut off. Analysing the conformal time as well as universe's age as infrared cut-offs, we explore the…

General Relativity and Quantum Cosmology · Physics 2020-12-29 Umesh Kumar Sharma , Gunjan Varshney , Vipin Chandra Dubey

In the present analysis, we explore a new version of dark energy called Barrow holographic dark energy within the framework modified gravity called $f(Q,T)$ gravity by adopting the simple homogeneous, isotropic, and spatially flat…

General Relativity and Quantum Cosmology · Physics 2024-08-09 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , K Ghaderi

In the framework of entropic cosmology, entropic forces arising at the cosmological horizon have been proposed as an alternative mechanism to explain the Universe's current accelerated phase. However, recent studies have shown that, under…

General Relativity and Quantum Cosmology · Physics 2025-10-02 Giuseppe Gaetano Luciano

Both the Barrow and Tsallis $\delta$ entropies are one-parameter generalizations of the black-hole entropy, with the same microcanonical functional form. The ensuing deformation is quantified by a dimensionless parameter $\Delta$, which in…

General Relativity and Quantum Cosmology · Physics 2024-10-28 Petr Jizba , Gaetano Lambiase , Giuseppe Gaetano Luciano , Leonardo Mastrototaro

We investigate the thermodynamic and phenomenological implications of a cosmological model governed by fractional entropy applied to the apparent horizon of a flat Friedmann-Lema\^{i}tre-Robertson-Walker (FLRW) universe. By utilizing the…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Miguel Cruz , Diego da Silva , Simón González , Samuel Lepe , Joel Saavedra , Manuel Gonzalez-Espinoza

Applying the modified Barrow entropy, inspired by the quantum fluctuation effects, to the cosmological background, and using thermodynamics-gravity conjuncture, the Friedmann equations get modified as well. In this paper, we explore the…

General Relativity and Quantum Cosmology · Physics 2024-12-18 M. Motaghi , A. Sheykhi , E. Ebrahimi

The Cosmological Problem is considered in a five-dimensional (bulk) manifold with two time coordinates, obeying vacuum Einstein field equations. The evolution formalism is used there, in order to get a simple form of the resulting…

General Relativity and Quantum Cosmology · Physics 2019-02-27 Carles Bona , Miguel Bezares , Bartolomé Pons-Rullan , Daniele Viganò

Deviations from the area law of the horizon entropy, in the cosmological setup, are known to lead to modified Friedmann equations governing the evolution of the universe. In this work, we propose that such modifications need not be…

General Relativity and Quantum Cosmology · Physics 2026-02-19 Amir A. Khodahami , Ahmad Sheykhi

We consider the evolution of a flat Friedmann-Roberstson-Walker Universe in a higher derivative theories, including $\alpha R^{2}$ terms to the Einstein-Hilbert action in the presence of a variable gravitational and cosmological constants.…

General Relativity and Quantum Cosmology · Physics 2014-11-17 P. S. Debnath , B. C. Paul

The cosmological term is assumed to be a function of time such as $\Lambda =Ba^{-2}$ where a(t) means the scale factor of standard cosmology. Analytical solutions for radiation dominated epoch and open universe are found. For closed…

High Energy Physics - Theory · Physics 2007-05-23 Carlos Pinheiro , F. C. Khanna

In this paper we suppose that the cosmological constant will change when the universe expends. For a general consideration, the cosmological constant is assumed to be a function of scale factor and Hubble constant. According to the ADM…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-03 Jin-Zhang Tang , Qiang Xu

We investigate the evolution of a spatially flat Friedmann-Robertson-Walker (FRW) universe in the framework of scalar non-metricity theory of gravity. In the model, we consider dark matter (DM) and dark energy (DE) described by the scalar…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Bikash Chandra Roy , Bikash Chandra Paul

One of the most outstanding problems of the standard model of cosmology today is the problem of cosmological constant/dark energy. It corresponds to about 73 per cent of the energy content of the universe gone missing. I hereby postulate a…

General Physics · Physics 2012-10-08 Serkan Zorba

We consider a variant of the brane-world model in which the universe is the direct product of a Friedmann, Robertson-Walker (FRW) space and a compact hyperbolic manifold of dimension $d\geq2$. Cosmology in this space is particularly…

High Energy Physics - Theory · Physics 2009-10-31 Glenn D. Starkman , Dejan Stojkovic , Mark Trodden

Bounce cosmological models containing a dark viscous fluid in a spatially flat Friedmann-Robertson-Walker (FRW) universe are considered. The universe evolution is described in terms of generalized equation of state (EoS) parameters, in…

General Relativity and Quantum Cosmology · Physics 2024-11-19 E. Elizalde , A. V. Yurov , A. V. Timoshkin

Evolution of the scale factor a(t) in Friedmann models (those with zero pressure and a constant cosmological term Lambda) is well understood, and elegantly summarized in the review of Felten and Isaacman [Rev. Mod. Phys. 58, 689 (1986)].…

Astrophysics · Physics 2008-11-26 J. M. Overduin , F. I. Cooperstock

We investigate the generation of baryon asymmetry from the corrections brought about in the Friedman equations due to Barrow entropy. In particular, by applying the gravity-thermodynamics conjecture one obtains extra terms in the Friedmann…

General Relativity and Quantum Cosmology · Physics 2022-06-28 Giuseppe Gaetano Luciano , Emmanuel N. Saridakis

We disclose the thermodynamical properties of the apparent horizon in a nonsingular universe. We take into account the zero-point length correction to the gravitational potential and derive the modified entropy expression that includes…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Ahmad Sheykhi , Leila Liravi , Kimet Jusufi