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Related papers: Do f(R) theories matter?

200 papers

One of the most interesting and current phenomenological extensions of General Relativity is the so-called $f (R)$ class of theories; a natural generalization of this includes an explicit non-minimal coupling between matter and curvature.…

General Relativity and Quantum Cosmology · Physics 2011-11-16 J. Páramos

Theories with a non-minimal coupling between the space-time curvature and matter fields introduce an extra force due to the non-conservation of the matter energy momentum. In the present work the theoretical consistency of such couplings is…

General Relativity and Quantum Cosmology · Physics 2013-10-02 Nicola Tamanini , Tomi S. Koivisto

In this contribution one examines the generalization of the $f(R)$ theories of gravity where one introduces a non-minimal coupling between curvature and matter. This model has new and interesting features. %, specially concerning the energy…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Orfeu Bertolami , Miguel Carvalho Sequeira

The connection between $f(R)$ theories of gravity and scalar-tensor models with a "physical" metric coupled to the scalar field is well known. In this work, we pursue the equivalence between a suitable scalar theory and a model that…

General Relativity and Quantum Cosmology · Physics 2009-01-01 O. Bertolami , J. Páramos

This study examines how inflationary dynamics are affected by $f(R)$ theories with a non-minimal coupling between matter and curvature. Both positive and negative corrections to the minimal coupling of General Relativity are considered, and…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Miguel Barroso Varela , Orfeu Bertolami , Andreas Mantziris

We examine an extension of General Relativity with an explicit non-minimal coupling between matter and curvature. The purpose of this work is to present an overview of the implications of the latter to various contexts, ranging from…

General Relativity and Quantum Cosmology · Physics 2014-01-20 Orfeu Bertolami , Jorge Páramos

In this work, we further study a metric modified theory of gravity which contains a non-minimal coupling to matter, more precisely, we assume two functions of the scalar curvature, $f_1$ and $f_2$, where the first one generalises the…

General Relativity and Quantum Cosmology · Physics 2021-03-31 María Ortiz-Baños , Mariam Bouhmadi-López , Ruth Lazkoz , Vincenzo Salzano

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 objective of this work is to present the effects of a nonminimally coupled model of gravity on a Solar System short range regime. For this reason, this study is only valid when the cosmological contribution is considered irrelevant. The…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-11 Nuno Castel-Branco

Recently there has been a proposal for modified gravitational f(R) actions which include a direct coupling between the matter action and the Ricci scalar, R. Of particular interest is the specific case where both the action and the coupling…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Thomas P. Sotiriou

In this work we show that the gravity lagrangian f(R) at relatively low curvatures in both metric and Palatini formalisms is a bounded function that can only depart from the linearity within the limits defined by well known functions. We…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Gonzalo J. Olmo

We extend the analysis of Chiba, Smith and Erickcek \cite{CSE} of Solar System constraints on $f(R)$ gravity to a class of nonminimally coupled (NMC) theories of gravity. These generalize $f(R)$ theories by replacing the action functional…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Orfeu Bertolami , Riccardo March , Jorge Páramos

It is shown that a non-minimal coupling between the scalar curvature and the matter Lagrangian density may account for the accelerated expansion of the Universe and provide, through mimicking, for a viable unification of dark energy and…

General Relativity and Quantum Cosmology · Physics 2014-11-20 O. Bertolami , P. Frazao , J. Páramos

Recently, in the context of $f(R)$ modified theories of gravity, a new type of model has been proposed where one directly couples the scalar curvature to matter. As any model in $f(R)$ theory, there are certain conditions which have to be…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Orfeu Bertolami , Miguel Carvalho Sequeira

In this work, we review a plethora of modified theories of gravity with generalized curvature-matter couplings. The explicit nonminimal couplings, for instance, between an arbitrary function of the scalar curvature $R$ and the Lagrangian…

General Relativity and Quantum Cosmology · Physics 2014-07-29 Tiberiu Harko , Francisco S. N. Lobo

We perform a phase space analysis of a non-minimally coupled modified gravity theory with the Lagrangian density of the form $\frac{1}{2} f_{1}(R)+[1+\lambda f_{2}(R)]{{\cal{L}}_{m}}$, where $f_1(R)$ and $f_2(R)$ are arbitrary functions of…

General Relativity and Quantum Cosmology · Physics 2014-06-03 Tahereh Azizi , Emad Yaraie

We examine $f(R, \text{Matter})$ theories that directly couple the curvature $R$ or $R_{\mu\nu}$ with the matter sector in the action, in addition to the universal coupling. We argue that if the matter sector includes the Standard Model…

General Relativity and Quantum Cosmology · Physics 2024-06-04 Osmin Lacombe , Shinji Mukohyama , Josef Seitz

In this paper we study the effects of $f(R)$ Theories of Gravity on Solar System gravitational tests. In particular, starting from an exact solution of the field equation in vacuum, in the Palatini formalism, we work out the effects that…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Matteo Luca Ruggiero , Lorenzo Iorio

In this proceeding, we review modified theories of gravity with a curvature-matter coupling between an arbitrary function of the scalar curvature and the Lagrangian density of matter. This explicit nonminimal coupling induces a…

General Relativity and Quantum Cosmology · Physics 2022-09-20 Francisco S. N. Lobo , Tiberiu Harko

The "measurability" of the non-minimal coupling is discussed in the context of the effective field theory of gravity. Although there is no obvious motive for excluding a non-minimal scalar coupling from the theory, we conclude that for…

High Energy Physics - Theory · Physics 2009-10-31 A. Flachi , D. J. Toms
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