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Related papers: Rindler type acceleration in f(R) gravity

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A particular form of the C-metric is investigated, giving it a non-standard interpretation and removing any singularity at $r = 0$. In the weak field limit of the accelerating black hole, the proper acceleration $A$ of a static observer is…

General Relativity and Quantum Cosmology · Physics 2019-01-28 Hristu Culetu

An inhomogeneous fluid in accelerated motion is investigated. When the velocity field $v(x)$ is not constant, the geometry viewed by a static observer is curved, as if the observer were immersed in a gravitational field. A…

General Relativity and Quantum Cosmology · Physics 2020-03-11 Hristu Culetu

We explore the shifted $f(R) (\propto R^{1+\delta})$ model with ${\delta}$ as a distinguishing physical parameter for the study of constraints at local scales. The corresponding dynamics confronted with different geodesics (null and…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-05 Vipin Kumar Sharma , Murli Manohar Verma

Several features of electrostatics of point charged particles in a weak, homogeneous, gravitational field are discussed using the Rindler metric to model the gravitational field. Some previously known results are obtained by simpler and…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Hamsa Padmanabhan , T. Padmanabhan

Gravity can be regarded as a consequence of local Lorentz (LL) symmetry, which is essential in defining a spinor field in curved spacetime. The gravitational action may admit a zero-field limit of the metric and vierbein at a certain…

High Energy Physics - Theory · Physics 2020-12-23 Shinya Matsuzaki , Shota Miyawaki , Kin-ya Oda , Masatoshi Yamada

The field equations of a generalized $f(R)$ type gravity model, in which there is an arbitrary coupling between matter and geometry, are obtained. The equations of motion for test particles are derived from a variational principle in the…

General Relativity and Quantum Cosmology · Physics 2009-05-26 T. Harko

Gravitational field equations in Randers-Finsler space of approximate Berwald type are investigated. A modified Friedmann model is proposed. It is showed that the accelerated expanding universe is guaranteed by a constrained Randers-Finsler…

General Relativity and Quantum Cosmology · Physics 2009-05-29 Zhe Chang , Xin Li

The $f(R)$ gravity theories provide an alternative way to explain the current cosmic acceleration without a dark energy matter component. If gravity is governed by a $f(R)$ theory a number of issues should be reexamined in this framework,…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-02 M. J. Reboucas , J. Santos

We consider generalized energy conditions in modified theories of gravity by taking into account the further degrees of freedom related to scalar fields and curvature invariants. The latter are usually recast as generalized {\it geometrical…

General Relativity and Quantum Cosmology · Physics 2014-02-14 Salvatore Capozziello , Francisco S. N. Lobo , José P. Mimoso

It is shown that the acceleration of the universe can be understood by considering a F(T) gravity models. For these F(T) gravity models, a variant of the accelerating cosmology reconstruction program is developed. Some explicit examples of…

General Relativity and Quantum Cosmology · Physics 2011-09-23 Ratbay Myrzakulov

The Raychaudhuri equation enables to examine the whole spacetime structure without specific solutions of Einstein's equations, playing a central role for the understanding of the gravitational interaction in Cosmology. In General…

General Relativity and Quantum Cosmology · Physics 2017-03-16 Crislane S. Santos , Janilo Santos , Salvatore Capozziello , Jailson S. Alcaniz

We investigate equations of motion and future singularities of $f(R,T)$ gravity where $R$ is the Ricci scalar and $T$ is the trace of stress-energy tensor. Future singularities for two kinds of equation of state (barotropic perfect fluid…

General Relativity and Quantum Cosmology · Physics 2018-08-21 Behrouz Mirza , Fatemeh Oboudiat

We study $f(R)$ gravity models in the language of scalar-tensor theories. The correspondence between $f(R)$ gravity and scalar-tensor theories is revisited since $f(R)$ gravity is a subclass of Brans-Dicke models, with a vanishing coupling…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Joseph Ntahompagaze , Amare Abebe , Manasse Mbonye

In this paper we have derived the behavior of deceleration parameter with respect to redshift in context of f(R) gravity in vacuum using Taylor expansion of derivative of action. Here we have obtained that the two first terms in Taylor…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Solmaz Asgari , Reza Saffari

Different (not only by sign) affine connections are introduced for contravariant and covariant tensor fields over a differentiable manifold by means of a non-canonical contraction operator, defining the notion dual bases and commuting with…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Manoff

We consider $f\left(R\right) $-gravity in a Friedmann-Lema\^itre-Robertson-Walker spacetime with zero spatial curvature. We apply the Killing tensors of the minisuperspace in order to specify the functional form of $f\left(R\right) $ and…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Andronikos Paliathanasis

The issues of quintessence and cosmic acceleration can be discussed in the framework of $F(R, {\cal G})$ theories of gravity where $R$ is the Ricci curvature scalar and ${\cal G}$ is the Gauss-Bonnet topological invariant. It is possible to…

General Relativity and Quantum Cosmology · Physics 2015-05-06 Mariafelicia De Laurentis

Within the weak-field approximation of general relativity, new exact solutions are derived for the gravitational field of a mass moving with arbitrary velocity and acceleration. A mass having a constant velocity greater than 3^-1/2 times…

General Relativity and Quantum Cosmology · Physics 2009-02-10 F. S. Felber

A main issue in cosmology and astrophysics is whether the dark sector phenomenology originates from particle physics, then requiring the detection of new fundamental components, or it can be addressed by modifying General Relativity.…

General Relativity and Quantum Cosmology · Physics 2022-02-22 Salvatore Capozziello , Carlo Alberto Mantica , Luca Guido Molinari

In this work, we investigate for an analytical solution under modified gravity theory, specifically the $f(R,T)$ gravity for two different eras, i.e., matter and dark energy dominated accelerating universe from completely geometrical and…

General Relativity and Quantum Cosmology · Physics 2023-12-12 Arijit Panda , Surajit Das , Goutam Manna , Saibal Ray
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