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The problem of coupling between spin and torsion is analysed from a Lyra's manifold background for scalar and vector massive fields using the Duffin-Kemmer-Petiau (DKP) theory. We found the propagation of the torsion is dynamical, and the…

High Energy Physics - Theory · Physics 2007-05-23 R. Casana , C. A. M. de Melo , B. M. Pimentel

We present a novel theory of gravity, namely, an extension of symmetric teleparallel gravity. This is done by introducing a new class of theories where the nonmetricity $Q$ is coupled nonminimally to the matter Lagrangian. This nonminimal…

General Relativity and Quantum Cosmology · Physics 2019-01-04 Francisco S. N. Lobo , Tiberiu Harko , Tomi S. Koivisto , Gonzalo J. Olmo , Diego Rubiera-Garcia

We present a general formulation of the theory for a non-minimally coupled perfect fluid in which both conformal and disformal couplings are present. We discuss how such non-minimal coupling is compatible with the assumptions of a perfect…

General Relativity and Quantum Cosmology · Physics 2015-10-20 Dario Bettoni , Stefano Liberati

A system of field equations for an Einstein-Maxwell model with $RF^2$-type nonminimal coupling in a non-Riemannian space-time with a non-vanishing torsion is derived and the resulting field equations are expressed in terms of the Riemannian…

General Relativity and Quantum Cosmology · Physics 2015-10-28 Ahmet Baykal , Tekin Dereli

In this contribution, we start off from a fully relativistic description of a single electron non-minimally coupled to an external electromagnetic field. Making direct use of the field equation, instead of canonically deriving from the…

Mesoscale and Nanoscale Physics · Physics 2020-02-24 Rodrigo Turcati , Carlos Andres Bonilla Quintero , José Abdalla Helayël-Neto , Enrique Arias

Gravitational models with non-minimal couplings involving functions of the matter Lagrangian and curvature have become popular in recent decades. By coupling the matter Lagrangian directly to the gravitational Lagrangian, one hopes to…

General Relativity and Quantum Cosmology · Physics 2026-05-18 Christian G. Boehmer , Erik Jensko , Eissa Al-Nasrallah

This work extends the proof of a local version of the linearized second law involving an entropy current with non-negative divergence by including the arbitrary non-minimal coupling of scalar and $U(1)$ gauge fields with gravity. In recent…

High Energy Physics - Theory · Physics 2022-12-08 Parthajit Biswas , Prateksh Dhivakar , Nilay Kundu

In the framework of teleparallel equivalent of general relativity, we study a gravity theory where a scalar field beyond its minimal coupling, is also coupled with the vector torsion through a non-minimal derivative coupling. After a…

General Relativity and Quantum Cosmology · Physics 2016-12-14 Behnaz Fazlpour

Gauge fields are described on an Riemann-Cartan space-time by means of tensor-valued differential forms and exterior calculus. It is shown that minimal coupling procedure leads to a gauge invariant theory where gauge fields interact with…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Alberto Saa

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

We will consider the most general least-order torsional completion of gravity with electrodynamics for the Dirac matter fields, and we study the effects that the torsion-spin coupling will have in inducing self-interactions among the…

General Relativity and Quantum Cosmology · Physics 2014-12-30 Luca Fabbri

The true nature of gravity is a remarkable open problem in Gravitation. Theoretical and observational motivations open the avenue of alternative theories of gravity. One possibility resorts to nonminimal couplings and non-metricity…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Cláudio Gomes

In this work we aim to revive the interest for non-minimal derivative coupling theories of gravity, in light of the GW170817 event. These theories include a string motivated non-minimal kinetic term for the scalar field of the form $\sim…

General Relativity and Quantum Cosmology · Physics 2024-02-06 V. K. Oikonomou

In this study, we explore how a non-minimal coupling between dark matter and gravity can affect the behavior of dark matter in galaxy clusters. We have considered the case of a disformal coupling, which leads to a modification of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-30 Saboura Zamani , Vincenzo Salzano , Dario Bettoni

We construct the theoretical base for the search of the possible experimental manifestations of the torsion field at low energies. The weakrelativistic approximation to the Dirac equation in an external torsion field is considered. For the…

High Energy Physics - Theory · Physics 2007-05-23 V. G. Bagrov , I. L. Buchbinder , I. L. Shapiro

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

A non-minimal coupling of Weyl curvatures to electromagnetic fields is considered in Brans-Dicke-Maxwell theory. The gravitational field equations are formulated in a Riemannian spacetime where the spacetime torsion is constrained to zero…

General Relativity and Quantum Cosmology · Physics 2020-04-14 Tekin Dereli , Yorgo Senikoglu

The non-minimal coupling of fermions to a background responsible for the breaking of Lorentz symmetry is introduced in Dirac's equation; the non-relativistic regime is contemplated, and the Pauli's equation is used to show how an…

High Energy Physics - Theory · Physics 2011-09-13 H. Belich , T. Costa-Soares , M. M. Ferreira , J. A. Helayel-Neto

We investigate two classes of non-minimally coupled curvature-matter models in the FLRW universe with a perfect fluid and analyze their cosmological implications using Supernova Ia, Observed Hubble Data, and Baryon Acoustic Oscillation…

General Relativity and Quantum Cosmology · Physics 2024-12-31 Anirban Chatterjee , Akshay Panda , Abhijit Bandyopadhyay

We study inflationary scenarios driven by a scalar field in the presence of a non-minimal coupling between matter and curvature. We show that the Friedmann equation can be significantly modified when the energy density during inflation…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Cláudio Gomes , João G. Rosa , Orfeu Bertolami