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Related papers: Friedmann equations for deformed entropic gravity

200 papers

In this paper we continue the study of the physical consequences of our modified black hole entropy formula in expanding spacetimes. In particular, we apply the new formula to apparent horizons of Friedmann expanding universes with zero,…

High Energy Physics - Theory · Physics 2016-03-08 Stefano Viaggiu

We present a first attempt to apply the approach of deformation quantization to linearized Einstein's equations. We use the analogy with Maxwell equations to derive the field equations of linearized gravity from a modified Maxwell…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Hernando Quevedo , Julio G. Tafoya

We show that derivation of Friedmann's equations from the Einstein-Hilbert action, paying attention to the requirements of isotropy and homogeneity during the variation, leads to a different interpretation of pressure than what is typically…

General Relativity and Quantum Cosmology · Physics 2021-07-15 Kevin S. Croker , Joel L. Weiner

We investigate torsion-driven cosmological dynamics within the framework of Einstein-Cartan gravity using the De Donder-Weyl Hamiltonian formalism, where the tetrad and Lorentz connection act as independent variables and the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2026-02-18 Aarav Shah , M. Yu. Khlopov , M. Krasnov

We investigate the cosmological aspects of the most general parity preserving Metric-Affine Gravity theory quadratic in torsion and non-metricity in the presence of a cosmological hyperfluid. The equations of motion are obtained by varying…

General Relativity and Quantum Cosmology · Physics 2022-01-13 Damianos Iosifidis , Lucrezia Ravera

We briefly describe the modified Friedmann equations for Einstein-Aether gravity theory and we find the effective density and pressure. The purpose of our present work is to reconstruction of Einstein-Aether Gravity from other modified…

General Relativity and Quantum Cosmology · Physics 2014-09-10 Chayan Ranjit , Ujjal Debnath

The paper deals with universal thermodynamics for FRW model of the universe bounded by apparent (or event) horizon. Assuming Hawking temperature on the horizon, the unified first law is examined on the horizon for different gravity…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Saugata Mitra , Subhajit Saha , Subenoy Chakraborty

A modified-gravity theory is considered with a four-form field strength F, a variable gravitational coupling parameter G(F), and a standard matter action. This theory provides a concrete realization of the general vacuum variable q as the…

General Relativity and Quantum Cosmology · Physics 2009-11-13 F. R. Klinkhamer , G. E. Volovik

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

Applying Clausius relation, $\delta Q=TdS$, to apparent horizon of a FRW universe with any spatial curvature, and assuming that the apparent horizon has temperature $T=1/(2\pi \tilde {r}_A)$, and a quantum corrected entropy-area relation,…

High Energy Physics - Theory · Physics 2008-11-26 Rong-Gen Cai , Li-Ming Cao , Ya-Peng Hu

In this work, we derive a generalized modified Friedmann equation based on an entropy-area relation that incorporates established modifications, such as volumetric, linear, and logarithmic terms, in addition to novel entropic modifications…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Javier Chagoya , I. Díaz-Saldaña , Mario H. Amante , J. C. López-Domínguez , M. Sabido

We derive the modified Friedmann equation corresponding to the power-law corrected entropy-area relation $S_{\rm A}=\frac{A}{4}[1-K_{\alpha} A^{1-\frac{\alpha}{2}}]$ which is motivated by the entanglement of quantum fields in and out of the…

General Physics · Physics 2011-09-07 K. Karami , A. Abdolmaleki , N. Sahraei , S. Ghaffari

We investigate the Friedmann-Robertson-Walker (FRW) universe (containing dark energy) as a non-equilibrium (irreversible) thermodynamical system by considering the power-law correction to the horizon entropy. By taking power-law entropy…

General Physics · Physics 2011-12-14 M. Umar Farooq , Mubasher Jamil

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

Considering the corrected Unruh temperature as well as the entropic force perspective of gravity, we are able to derive the modification of the Newton's law of gravity. In addition, we also investigate the effects of the highest achievable…

General Relativity and Quantum Cosmology · Physics 2018-04-16 H. Moradpour , A. Amiri , A. Sheykhi

This paper investigates the flat Friedmann-Lema$\hat{\imath}$tre-Robertson-Walker (FLRW) cosmological model using a suitable parameterization represented as a differential equation concerning the energy density of the scalar field,…

General Relativity and Quantum Cosmology · Physics 2024-04-30 J. K. Singh , Shaily , Harshna Balhara , Sushant G. Ghosh , Sunil D. Maharaj

We use the Brans-Dicke theory from the framework of General Relativity (Einstein frame), but now the total energy momentum tensor fulfills the following condition $\rm <[\{1}{\phi}T^{\mu \nu M}+T^{\mu \nu}(\phi)>]_{;\nu}=0$. We take as a…

General Relativity and Quantum Cosmology · Physics 2013-05-09 Juan M. Ramírez , J. Socorro

In previous works, entropic gravity and ungravity have been considered as possible solutions to the dark energy and dark matter problems. To test the viability of these models, modifications to planetary orbits are calculated for ungravity…

General Relativity and Quantum Cosmology · Physics 2025-10-09 G. Pérez Cuéllar , M. Sabido

The investigation of quantum gravity effects in order to avoid the big bang singularity is a requisite, so that the idea of oscillating universes is introduced as an alternative for standard cosmological model. Therefore, the Friedmann…

General Relativity and Quantum Cosmology · Physics 2018-04-18 Amin. Salehi , Mojtaba. Mahmoudi fard

We study a noncommutative deformation of general relativity where the gravitational field is described by a matrix-valued symmetric two-tensor field. The equations of motion are derived in the framework of this new theory by varying a…

General Relativity and Quantum Cosmology · Physics 2011-02-17 Guglielmo Fucci , Ivan G. Avramidi
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