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Related papers: Cosmic acceleration in entropic cosmology

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In this paper, we investigate a scenario in which late time cosmic acceleration might arise due to coupling between dark matter and baryonic matter without resorting to dark energy or large scale modification of gravity associated with…

General Relativity and Quantum Cosmology · Physics 2019-06-18 Abhineet Agarwal , R. Myrzakulov , S. K. J. Pacif , M. Sami , Anzhong Wang

In this work, we investigate the cosmological dynamics of an anisotropic Universe within the framework of $f(R,T)$ gravity by incorporating pressureless dark matter and the dark energy models. The analysis is carried out in a Bianchi type-I…

General Relativity and Quantum Cosmology · Physics 2026-05-13 S. H. Shekh , N. Myrzakulov , Anirudh Pradhan , M. Zeyauddin

In `entropic cosmology', instead of a cosmological constant $\Lambda$, an extra driving term is added to the Friedmann equation and the acceleration equation, taking into account the entropy and the temperature on the horizon of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-14 Nobuyoshi Komatsu , Shigeo Kimura

The present article analyses the impact on cosmology, in particular on the evolution of cosmological perturbations, of the existence of extra-dimensions. The model considered here is that of a five-dimensional Anti-de Sitter spacetime where…

High Energy Physics - Theory · Physics 2009-10-31 David Langlois

In this work, we have considered a minimally modified gravity theory that effectively reproduces VCDM-like behavior to investigate its cosmological implications. The model parameters are constrained using a combination of CC, RSD, DESI BAO…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Sai Swagat Mishra , Soumya Kanta Bhoi , P. K. Sahoo

We trace the origin of the cosmological constant problem to the assumption that Newton's constant $G$ sets the scale for cosmology. And then we show that once this assumption is relaxed, the very same cosmic acceleration which has served to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Philip D. Mannheim

In a recent model Choudhury proposed that a collapsing matter generates an adiabatic pressure which can be used to explain the acceleration of the physical universe under certain approximation. In this work we superimpose the core pressure…

General Relativity and Quantum Cosmology · Physics 2008-05-26 A. M. Haruar Rashid , A. L. Choudhury

We explore the dynamics and evolution of the Universe at early and late times, focusing on both dark energy and extended gravity models and their astrophysical and cosmological consequences. Modified theories of gravity not only provide an…

In order to explain the Late-times accelerated expansion of the Universe we must appeal to some form of Dark Energy. In the standard model of cosmology, the latter is interpreted as a Cosmological Constant $\Lambda$. However, for a number…

General Relativity and Quantum Cosmology · Physics 2021-02-18 Leonardo Giani

We discuss how entropy bounds, which are not respected in the standard cosmology, constrain the parameters of a previously suggested cosmology with a finite total mass. In that alternative cosmology the matter density was postulated to be a…

General Relativity and Quantum Cosmology · Physics 2016-02-09 L. Clavelli

Plane symmetric cosmological models are investigated with or without any dark energy components in the field equations. Keeping an eye on the recent observational constraints concerning the accelerating phase of expansion of the universe,…

General Relativity and Quantum Cosmology · Physics 2015-02-24 S. K. Tripathy , K. L. Mahanta

In this paper, we present the cosmological scenario obtained from $f(R,T)$ gravity by using an exponential dependence on the trace of the energy-momentum tensor. With a numerical approach applied to the equations of motion, we show several…

General Relativity and Quantum Cosmology · Physics 2019-11-11 G. Ribeiro , R. Sfair , P. H. R. S. Moraes , J. R. L. Santos , A. de Souza Dutra

A discrete space-time structure lying at about the Planck scale may become manifest in the form of very small violations of the conservation of the matter energy-momentum tensor. In order to include such kind of violations, forbidden within…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-15 Susana J. Landau , Micol Benetti , Alejandro Perez , Daniel Sudarsky

In this paper, we have studied an interacting dark energy model. We have assumed the gravitational interaction between the matter fields i.e. between barotropic fluid and the dark energy. The dark energy evolution within the framework of…

General Relativity and Quantum Cosmology · Physics 2023-04-03 Keshav Ram Mishra , Shibesh Kumar Jas Pacif , Rajesh Kumar , Kazuharu Bamba

In this paper, we will analyse the cosmological models in Einstein-aether gravity, which is a modified theory of gravity in which a time-like vector field breaks the Lorentz symmetry. We will use this formalism to analyse different…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Antonio Pasqua , Surajit Chattopadhyay , Davood Momeni , Muhammad Raza , Ratbay Myrzakulov , Mir Faizal

Since viable $f(R)$ gravity models must reconcile early-universe inflation with late-time acceleration, we specifically study the dynamical behavior of such a theory during the matter-dominated to dark-energy-dominated transition epoch. By…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Siqi He , Weiqiang Yang , Hangyi Jin

The origin of the Universe's late-time accelerated expansion remains unknown. The General Relativistic Entropic Acceleration (GREA) theory offers a compelling alternative to $\Lambda$CDM, attributing cosmic acceleration to entropy growth…

We present a cosmological model arising from a gravitational theory with an infinite tower of higher-order curvature invariants that can reproduce the entire evolution of the Universe: from inflation to late-time acceleration, without…

General Relativity and Quantum Cosmology · Physics 2022-02-10 Luisa G. Jaime , Gustavo Arciniega

The existence of 'peculiar' velocities due to the formation of cosmic structure marks a point of discord between the real Universe and the usually assumed Friedmann-Lema\'{i}tre-Robertson-Walker metric which accomodates only the smooth…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-09 Roya Mohayaee , Mohamed Rameez , Subir Sarkar

Brane cosmology presents many interesting possibilities including: phantom acceleration (w<-1), self-acceleration, unification of dark energy with inflation, transient acceleration, loitering cosmology, new singularities at which the Hubble…

Astrophysics · Physics 2008-11-25 Varun Sahni , Yuri Shtanov