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Related papers: F(R) gravity equation of state

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In this work we further extend the analysis of $f(R)$ theories of gravity in the metric formalism under the approach of a Thermodynamics analogy, proposed in arXiv:1911.04830v3. Here we assume a double-well inflationary potential in the…

General Relativity and Quantum Cosmology · Physics 2023-06-21 C. D. Peralta , S. E. Jorás

We construct spherically symmetric and static solutions in $F(R)$ gravity coupled with electromagnetic fields. The solutions include new types of black holes with electric and magnetic charges. We show that the higher-derivative terms make…

General Relativity and Quantum Cosmology · Physics 2023-03-22 G. G. L. Nashed , S. Nojiri

In the framework of ADM formalism, it is possible to find out eigenvalues of the WDW equation with the meaning of vacuum states, i.e. cosmological constants, for f(R) theories of gravity, where f(R) is a generic analytic function of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Capozziello , R. Garattini

We consider E. Verlinde's proposal that gravity is an entropic force -- we shall call this theory entropic gravity (EG) -- and reanalyze a recent claim that this theory is in contradiction with the observation of the gravitationally-bound…

High Energy Physics - Theory · Physics 2012-05-23 Masud Chaichian , Markku Oksanen , Anca Tureanu

The Gravity from Entropy (GfE) action posits that gravity that is fundamentally given by the information encoded in the interplay between matter and geometry. The GfE Lagrangian is given by the Geometric Quantum Relative Entropy (GQRE)…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Ginestra Bianconi

The Schwarzschild's black hole dynamics in presence of gravity is described on using the thermodynamic equations of state for contractile materials. Its entropy and temperature, obtained by using classical principles, reproduce the results…

General Relativity and Quantum Cosmology · Physics 2010-11-04 Fernando Porcelli , Giancarlo Scibona

In this work, we re-assess a class of black hole solutions in a global monopole spacetime in the framework of an $f(R)$-gravity model. Our main line of investigation consists in considering a region close enough to the black hole, but such…

The theory of f(R)-gravity is one of the theories of modified Einstein gravity. The vacuum solution, on the other hand, of the field equation is the solution for black hole geometry. We establish here an asymptotically flat rotating black…

General Relativity and Quantum Cosmology · Physics 2022-11-07 Arghya Ranjan Das , Banibrata Mukhopadhyay

Motivated by the analogy between the spacetime and the solid with inhomogeneous elasticity modulus, we present an alternative method to obtain the field equation of any diffeomorphism-invariant gravity, by extremizing the constructed…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Shao-Feng Wu , Bin Wang , Xian-Hui Ge , Guo-Hong Yang

We suggest a mechanism for the emergence of classical dynamical spacetime from an underlying quantum gravitational system. This is an example of a more general process, which we name micro-equilibration, and which can be thought of as local…

High Energy Physics - Theory · Physics 2019-05-29 Veronika E. Hubeny , Massimiliano Rota

The main objective of this article is to derive a new set of gravitational field equations and to establish a new unified theory for dark energy and dark matter. The new gravitational field equations with scalar potential $\varphi$ are…

General Physics · Physics 2013-08-20 Tian Ma , Shouhong Wang

We consider the motion of test particles in the spacetime of a black hole in f(R) gravity. The complete set of analytic solutions of the geodesic equation in the spacetime of this black hole are presented. The geodesic equations are solved…

General Relativity and Quantum Cosmology · Physics 2015-08-19 Saheb Soroushfar , Reza Saffari , Jutta Kunz , Claus Lämmerzahl

The two surprising features of gravity are (a) the principle of equivalence and (b) the connection between gravity and thermodynamics. Using principle of equivalence and special relativity in the {\it local inertial frame}, one could obtain…

High Energy Physics - Theory · Physics 2009-11-07 T. Padmanabhan

The description of gravity in the form of an embedding theory is based on the hypothesis that our space-time is a four-dimensional surface in a flat ten-dimensional space. The choice of standard Einstein-Hilbert action leads in this case to…

General Relativity and Quantum Cosmology · Physics 2023-07-06 S. A. Paston , A. D. Kapustin

We investigate the corresponding relation between $f(R)$ gravity and holographic dark energy. We introduce a kind of energy density from $f(R)$ which has role of the same as holographic dark energy. We obtain the differential equation that…

General Physics · Physics 2014-01-20 Kh. Saaidi , A. Aghamohammadi

Quantized expressions for the gravitational energy and momentum are derived from a linearized theory of teleparallel gravity. The derivation relies on a second-quantization procedure that constructs annihilation and creation operators for…

General Relativity and Quantum Cosmology · Physics 2011-10-18 S. C. Ulhoa

Jacobson theorem (Ref. \cite{jacobson}) shows that Einstein gravity may be understood as a thermodynamical equation of state; a microscopic realization of this result is however lacking. In this paper, we propose that this may be achieved…

High Energy Physics - Theory · Physics 2011-05-19 Marcelo Botta Cantcheff

The black hole entropy formula applied to local Rindler horizon at each spacetime point has been used in the literature to derive the Einstein field equation as an equation of state of a thermodynamical system of spacetime. In the present…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S C Tiwari

Torsion and curvature could play a fundamental role in explaining cosmological dynamics. f(R)-gravity with torsion is an approach aimed to encompass in a comprehensive scheme all the Dark Side of the Universe (Dark Energy and Dark Matter).…

General Relativity and Quantum Cosmology · Physics 2014-11-20 S. Capozziello , S. Vignolo

Scalar-tensor $f(R)$ theory of gravity is considered in the framework of a simple inhomogeneous space-time model. In this we use the reconstruction technique to look for possible evolving wormhole solutions within viable $f(R)$ gravity…

General Relativity and Quantum Cosmology · Physics 2017-08-14 Subhra Bhattacharya , S. Chakraborty