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Related papers: Brane-world and loop cosmology from a gravity-matt…

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We consider a brane world scenario in which the bulk action is assumed to have the form of a generic function of the Ricci scalar $f(\mathcal{R})$ and derive the resulting Einstein field equations on the brane. In a constant curvature bulk…

General Relativity and Quantum Cosmology · Physics 2024-11-18 A. Borzou , H. R. Sepangi , S. Shahidi , R. Yousefi

We present a reconstruction of the Lagrangian for $f(R)$ gravity by using a massive scalar field. The scalar field is minimally coupled to the action of $f(R)$ gravity. We demonstrate the use of a theorem based on invertible point…

General Relativity and Quantum Cosmology · Physics 2020-02-06 Soumya Chakrabarti , Kazuharu Bamba , Jackson Levi Said

Braneworld scenarios are motivated by string/M-theory and can be characterized by the way in which they modify the conventional Friedmann equations of Einstein gravity. An alternative approach to quantum gravity, however, is the loop…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Edmund J. Copeland , James E. Lidsey , Shuntaro Mizuno

We reconstruct an $f(R)$ gravity model that gives rise to the particular $\Lambda$CDM background evolution of the universe. We find well-defined, real-valued analytical forms for the $f(R)$ model to describe the universe both in the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jian-hua He , Bin Wang

This work deals with modified gravity in five dimensional spacetime. We study a thick Palatini $f(R)$ brane, that is, a braneworld scenario described by an anti-de Sitter warped geometry with a single extra dimension of infinite extent,…

High Energy Physics - Theory · Physics 2015-12-09 D. Bazeia , L. Losano , R. Menezes , Gonzalo J. Olmo , D. Rubiera-Garcia

We present a new approach of the reconstruction method based on the use of the cosmic parameters instead of a time law for the scale factor. This allows the derivation and analysis of a set of new non-trivial cosmological solutions for…

General Relativity and Quantum Cosmology · Physics 2015-05-18 Sante Carloni , Rituparno Goswami , Peter K. S. Dunsby

We consider the cosmology of the Ricci-tensor-squared gravity in the Palatini variational approach. The gravitational action of standard general relativity is modified by adding a function f(R^abR_ab) to the Einstein-Hilbert action, and the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Baojiu Li , John D. Barrow , David F. Mota

We illustrate a general reconstruction procedure for mimetic gravity. Focusing on a bouncing cosmological background, we derive general properties that must be satisfied by the function $f(\Box\phi)$ implementing the limiting curvature…

General Relativity and Quantum Cosmology · Physics 2019-05-10 Marco de Cesare

Within the framework of geodetic brane gravity, the Universe is described as a 4-dimensional extended object evolving geodetically in a higher dimensional flat background. In this paper, by introducing a new pair of canonical fields…

General Relativity and Quantum Cosmology · Physics 2009-11-07 David Karasik , Aharon Davidson

In this manuscript, we present a number of fascinating explicit reconstructions for the $f(Q)$ gravity from the background of Friedmann-La\^imatre-Robertson-Walker (FLRW) evolution history. We find the more general functions of…

General Relativity and Quantum Cosmology · Physics 2022-10-25 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo

We present a novel theory of gravity by considering an extension of symmetric teleparallel gravity. This is done by introducing, in the framework of the metric-affine formalism, a new class of theories where the nonmetricity $Q$ is…

General Relativity and Quantum Cosmology · Physics 2018-10-31 Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo , Diego Rubiera-Garcia

The cosmological dynamics of a brane world scenario where the bulk action is taken as a generic function of the Ricci scalar is considered in a framework where the use of the $\mathbb{Z}_2$ symmetry and Israel junction conditions are…

General Relativity and Quantum Cosmology · Physics 2013-08-13 Zahra Haghani , Hamid Reza Sepangi , Shahab Shahidi

We propose a braneworld scenario in a modified symmetric teleparallel gravitational theory, where the dynamics for the gravitational field is encoded in the nonmetricity tensor rather than in the curvature. Assuming a single real scalar…

General Relativity and Quantum Cosmology · Physics 2022-08-31 J. E. G. Silva , R. V. Maluf , Gonzalo J. Olmo , C. A. S. Almeida

The fundamental plane (FP) of galaxies can be recovered in the framework of $f(R)$ gravity avoiding the issues related to dark matter to fit the observations. In particular, the power-law version $f(R)\propto R^n$, resulting from the…

Astrophysics of Galaxies · Physics 2016-10-12 V. Borka Jovanović , S. Capozziello , P. Jovanović , D. Borka

Cosmography is a useful tool to constrain cosmological models, in particular dark energy models. In the case of modified theories of gravity, where the equations of motion are generally quite complicated, cosmography can contribute to…

General Relativity and Quantum Cosmology · Physics 2010-12-23 Mariam Bouhmadi-Lopez , Salvatore Capozziello , Vincenzo F. Cardone

In this paper, we explore a reconstruction scheme in the background of the $f(T,\mathcal{T})$ gravity theory for different cosmological scenarios, where $T$ is the scalar torsion and $\mathcal{T}$ is the trace of the energy-momentum tensor.…

General Relativity and Quantum Cosmology · Physics 2023-10-17 Tuhina Ghorui , Prabir Rudra , Farook Rahaman

We investigate brane world models in higher-derivative gravity theories where the gravitational Lagrangian is an arbitrary function of the Ricci scalar. Making use of the conformal equivalence of such gravity models and Einstein-Hilbert…

High Energy Physics - Phenomenology · Physics 2009-11-11 M. Parry , S. Pichler , D. Deeg

Palatini $f(R)$ gravity is probably the simplest extension of general relativity (GR) and the simplest realization of a metric-affine theory. It has the same number of degrees of freedom as GR and, in vacuum, it is straightforwardly mapped…

General Relativity and Quantum Cosmology · Physics 2023-10-10 Alejandro Hernandez-Arboleda , Davi C. Rodrigues , Júnior D. Toniato , Aneta Wojnar

A variant of the accelerating cosmology reconstruction program is developed for $f(R)$ gravity. Reconstruction schemes in terms of e-foldings and by using an auxiliary scalar field are developed. An example of a model with a transient…

General Relativity and Quantum Cosmology · Physics 2013-01-11 Antonio Jesús López-Revelles

f(R)-theories of gravity are reviewed in the framework of the matter-antimatter asymmetry in the Universe. The asymmetry is generated by the gravitational coupling of heavy (Majorana) neutrinos with the Ricci scalar curvature. In order that…

High Energy Physics - Phenomenology · Physics 2015-06-23 G. Lambiase , S. Mohanty , L. Pizza
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