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Related papers: F(R) gravity's rainbow and its Einstein counterpar…

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Rainbow gravity modifies general relativity by introducing an energy dependent metric, which is expected to have a role in the quantum theory of black holes and in quantum gravity at Planck energy scale. We show that rainbow gravity can be…

General Relativity and Quantum Cosmology · Physics 2018-06-07 Maria Chiara Braidotti , Claudio Conti

With the successes of $f(R)$ theory as a neutral modification of Einstein's general relativity (GR), we continue our study in this field and attempt to find general %natural { neutral} and charged black hole (BH) solutions. In the previous…

General Relativity and Quantum Cosmology · Physics 2021-12-21 G. G. L. Nashed , Shin'ichi Nojiri

We consider a class of spherically symmetric spacetime to obtain some interesting solutions in F(R) gravity without matter field (pure gravity). We investigate the geometry of the solutions and find that there is an essential singularity at…

General Relativity and Quantum Cosmology · Physics 2014-03-03 S. H. Hendi , B. Eslam Panah , C. Corda

The entropic force attracts a lot of interest for its multifunctional properties. For instance, Einstein's field equation, Newton's law of gravitation and the Friedmann equation can be derived from the entropic force. In this paper,…

High Energy Physics - Theory · Physics 2020-07-01 Zhong-Wen Feng , Shu-Zheng Yang

Gravitational redshift is generally reported by most of the authors without considering the influence of the energy of the test particle using various spacetime geometries such as Schwarzschild, Reissner-Nordstrom, Kerr and Kerr-Newman…

General Physics · Physics 2017-10-06 Anuj Kumar Dubey , A. K. Sen , Bijoy Mazumdar

We re-examine a recently proposed scenario where the deformed dispersion relations associated with a flow of the spectral dimension to a UV value of 2 leads to a scale-invariant spectrum of cosmological fluctuations, without the need for…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Giovanni Amelino-Camelia , Michele Arzano , Giulia Gubitosi , Joao Magueijo

$f(R)$ theory is a modification of Einstein general relativity which has many interesting results in cosmology and astrophysics. To derive black hole solution in this theory is difficult due to the fact that it is fourth order differential…

General Relativity and Quantum Cosmology · Physics 2020-02-19 G. G. L. Nashed , Kazuharu Bamba

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

We extract exact charged black-hole solutions with flat transverse sections in the framework of D-dimensional Maxwell-f(T) gravity, and we analyze the singularities and horizons based on both torsion and curvature invariants. Interestingly…

High Energy Physics - Theory · Physics 2013-03-21 Salvatore Capozziello , P. A. Gonzalez , Emmanuel N. Saridakis , Yerko Vasquez

The gravity's rainbow function is derived in terms of a new varying speed of light (VSL) theory that varying velocity of light in the rainbow gravity becomes smaller when the energy of photons increases. In light of the new theory we…

General Relativity and Quantum Cosmology · Physics 2024-12-10 Ying-Jie Zhao , Xiaojie Li , Guang-Rui Yao , Yan-Fang Ji , Nisar Ahmad

By presenting a relation between average energy of the ensemble of probe photons and energy density of the Universe, in the context of {\it gravity's rainbow} or {\it doubly general relativity} scenario, we introduce a rainbow FRW Universe…

General Relativity and Quantum Cosmology · Physics 2015-12-15 M. Khodadi , Y. Heydarzade , K. Nozari , F. Darabi

In the presence of external, linear / nonlinear electromagnetic fields we integrate f(R) \sim R+2{\alpha}\surd(R+const.) gravity equations. In contrast to their Einsteinian cousins the obtained black holes are non-asymptotically flat with a…

General Relativity and Quantum Cosmology · Physics 2012-01-05 S. Habib Mazharimousavi , M. Halilsoy , T. Tahamtan

Confirming the existence of compact objects with a mass greater than $2.5M_{\odot}$ by observational results such as GW190814 makes that is possible to provide theories to justify these observational results using modified gravity. This…

General Relativity and Quantum Cosmology · Physics 2023-11-23 A. Bagheri Tudeshki , G. H. Bordbar , B. Eslam Panah

In this paper, we study the various cylindrical solutions (cosmic strings) in gravity's rainbow scenario. In particular, we calculate the gravitational field equations corresponding to energy-dependent background. Further, we discuss the…

General Relativity and Quantum Cosmology · Physics 2017-08-03 Davood Momeni , Sudhaker Upadhyay , Yerlan Myrzakulov , Ratbay Myrzakulov

In this paper, we investigate regular black hole solutions in the (2+1)-dimensional versions of General Relativity and $f(R, T)$ gravity, both coupled to nonlinear electrodynamics. By admitting that the matter content that generates such…

General Relativity and Quantum Cosmology · Physics 2025-08-18 Miguel A. S. Pinto , Roberto V. Maluf , Gonzalo J. Olmo

In the present work, we extend and generalize our previous work regarding the scale dependence applied to black holes in the presence of non-linear electrodynamics [1]. The starting point for this study is the Einstein-power-Maxwell theory…

General Relativity and Quantum Cosmology · Physics 2021-02-05 Angel Rincon , Ernesto Contreras , Pedro Bargueño , Benjamin Koch , Grigoris Panotopoulos

We consider a $f(R)$ gravity theory in $(2+1)$-dimensions with a self-interacting scalar field non-minimally coupled to gravity. Without specifying the form of the $f(R)$ function, solving the field equations we find that the Ricci scalar…

General Relativity and Quantum Cosmology · Physics 2022-02-18 Thanasis Karakasis , Eleftherios Papantonopoulos , Zi-Yu Tang , Bin Wang

In this note we explore a non-static spacetime in quantum regime in the background of $f(R)$ gravity. The time dependent Vaidya metric which represents the spacetime of a radiating body like star is studied in an energy dependent gravity's…

General Relativity and Quantum Cosmology · Physics 2020-04-22 Prabir Rudra

This work investigates some feasible regions for the existence of traversable wormhole geometries in $f(R,G)$ gravity, where $R$ and $G$ represent the Ricci scalar and the Gauss-Bonnet invariant respectively. Three different matter contents…

General Physics · Physics 2018-11-12 M. Farasat Shamir , Saeeda Zia

Doubly special relativity (DSR) is an effective model for encoding quantum gravity in flat spacetime. To incorporate DSR into general relativity, one could use gravity's rainbow, where the spacetime background felt by a test particle would…

General Relativity and Quantum Cosmology · Physics 2022-05-27 Yuzhou Tao , Benrong Mu , Siyuan Hui , Jun Tao