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Related papers: Entropic-force dark energy reconsidered

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In the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmological model, the energy conditions provides model-independent bounds on the behavior of the distance modulus. However, this method can not provide us the detailed information…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-20 Wen-Fei Liu , Jing Niu , Juan Li , Tong-Jie Zhang

The evolution of a flat, isotropic and homogeneous universe is studied. The background geometry in the early phases of the universe is conjectured to be filled with causal bulk viscous cosmological fluid and dark energy. The energy density…

General Relativity and Quantum Cosmology · Physics 2012-04-23 A. Tawfik

Physics invites the idea that space contains energy whose gravitational effect approximates that of Einstein's cosmological constant, Lambda; nowadays the concept is termed dark energy or quintessence. Physics also suggests the dark energy…

Astrophysics · Physics 2008-11-26 P. J. E. Peebles , Bharat Ratra

The Hubble constant $H_0$ is one of the important cosmological parameters measuring the expansion rate of our universe at present moment. Over the last couple of years, $H_0$ has created an enormous amount of debates interests in the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-29 Supriya Pan , Weiqiang Yang

Considering the power-law corrections to the black hole entropy, which appear in dealing with the entanglement of quantum fields inside and outside the horizon, the holographic energy density is modified accordingly. In this paper we study…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-08 A. Sheykhi , K. Karami , Mubasher Jamil , E. Kazemi , M. Haddad

In the last decades, a cosmological model that fits observations through a vast range of scales emerged. It goes under the name of ${\Lambda}$CDM. However, there are still challenging questions that remain unanswered by this model, such as…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-25 Michele Mancarella

In models where dark matter and dark energy interact non-minimally, the total amount of matter in a fixed comoving volume may vary from the time of recombination to the present time due to energy transfer between the two components. This…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-16 P. P. Avelino , H. M. R. da Silva

In this study, we consider three dark energy models in which $\Lambda$ is not constant, but has a dynamic nature that depends on the Hubble parameter $H$ and/or its time derivative $\dot{H}$. We analyze the generalized running vacuum model,…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Christine R. Farrugia , Joseph Sultana , Jurgen Mifsud

By considering the logarithmic correction to the energy density, we study the behavior of Hubble parameter in the holographic dark energy model. We assume that the universe is dominated by interacting dark energy and matter and the…

General Physics · Physics 2011-05-09 H. Mohseni Sadjadi , Mubasher Jamil

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

In Verlinde's entropic force scenario of gravity, Newton's laws and Einstein equations can be obtained from the first pinciples and general assumptions. However, the equipartition law of energy is invalid at very low temperatures. We show…

General Relativity and Quantum Cosmology · Physics 2011-08-04 Zhe Chang , Ming-Hua Li , Xin Li

We consider multidimensional cosmological model with a higher-dimensional product manifold M = R x R^{d_0} x H^{d_1}/\Gamma where R^{d_0} is d_0-dimensional Ricci-flat external (our) space and H^{d_1}/\Gamma is d_1-dimensional compact…

Astrophysics · Physics 2015-05-13 V. Baukh , A. Zhuk

A rare coincidence of scales in standard particle physics is needed to explain why $\Lambda$ or the negative pressure of cosmological dark energy (DE) coincides with the positive pressure $P_0$ of random motion of dark matter (DM) in bright…

Astrophysics · Physics 2009-11-13 HongSheng Zhao

While $\Lambda$CDM provides a good fit to cosmological data, it fails to address many of the outstanding questions in contemporary cosmology. Chief among these are the Hubble tension and the apparent dynamical nature of dark energy as…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-28 Amin Aboubrahim , Pran Nath

We derive a model of dark energy which evolves with time via the scale factor. The equation of state $\omega=(1-2\alpha)/(1+2\alpha)$ is studied as a function of a parameter $\alpha$ introduced in this model. In addition to the recent…

General Relativity and Quantum Cosmology · Physics 2017-06-20 Hemza Azri , A. Bounames

Two very different methods are used to estimate the magnitude of the effective cosmological constant / dark energy (for the present cosmic epoch). Their results agree with each other and are in agreement with observations. One method makes…

General Relativity and Quantum Cosmology · Physics 2017-06-15 Y. Jack Ng

Recently, Avik De and L.T. How claim that we have not followed an effective theory approach for $f(Q)$ gravity, missing relevant terms to compute the energy conditions [Phys. Rev. D 102, 024057 (2020)]. They also state that we did not…

General Relativity and Quantum Cosmology · Physics 2022-08-30 Sanjay Mandal , P. K. Sahoo , J. R. L. Santos

Cosmological models with two interacting fluids, each satisfying the strong energy condition, are studied in the framework of classical General Relativity. If the interactions are phenomenologically described by a power law in the scale…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Nelson Pinto-Neto , Bernardo M. O. Fraga

One of the most appealing approaches to ease the Hubble tension is the inclusion of an early dark energy (EDE) component that adds energy to the Universe in a narrow redshift window around the time of recombination and dilutes faster than…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Matteo Braglia , William T. Emond , Fabio Finelli , A. Emir Gumrukcuoglu , Kazuya Koyama

We present a $f(G,T)$ gravity-based reconstruction of Barrow Holographic Dark Energy (BHDE). This approach extends the conventional HDE model by replacing the Bekenstein-Hawking entropy with Barrow entropy, which encapsulates quantum…

General Relativity and Quantum Cosmology · Physics 2025-05-29 Giuseppe Gaetano Luciano
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