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Related papers: Slow-roll inflation in $f(T,\mathcal{T})$ modified…

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We consider the torsional completion of gravity with spinor and scalar fields: we show how in this environment conditions of extreme symmetry or specific approximations imply the scalar field to be constant, so that slow-roll takes place…

General Relativity and Quantum Cosmology · Physics 2017-07-07 Luca Fabbri

We present the coupling of the torsion scalar $T$ and the trace of energy-momentum tensor $\mathcal{T}$, which produces new modified $f(T,\mathcal{T})$ gravity. Moreover, we consider the functional form $f(T,\mathcal{T}) =\alpha…

General Relativity and Quantum Cosmology · Physics 2023-03-13 Simran Arora , Aaqid Bhat , P. K. Sahoo

We have investigated inflationary model constructed from minimally modified gravity (MMG) theories. The MMG theory in the form of $f({\bf H}) \propto {\bf H}^{1+p}$ gravity where, ${\bf H}$ is the Hamiltonian constraint in the Einstein…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-14 Jakkrit Sangtawee , Khamphee Karwan

We examine cosmological inflation in a broad family of scalar-tensor models characterized by scalar-dependent non minimal kinetic couplings and Gauss-Bonnet terms. Using a slow roll-approximation, we compute in detail theoretical…

High Energy Physics - Theory · Physics 2026-05-21 A. Belhaj , H. Es-Sobbahi , M. Oualaid , E. Torrente-Lujan

In present paper we propose further modification of $f(R,T)$-gravity (where $T$ is trace of energy-momentum tensor) by introducing higher derivatives matter fields. We discuss stability conditions in proposed theory and find restrictions…

General Relativity and Quantum Cosmology · Physics 2018-11-07 Petr V. Tretyakov

We study inflation in the framework of $f(T)$-gravity in the presence of a canonical scalar field. After reviewing the basic equations governing the background cosmology in $f(T)$-gravity, we turn to study the cosmological perturbations and…

General Relativity and Quantum Cosmology · Physics 2016-02-02 K. Rezazadeh , A. Abdolmaleki , K. Karami

The reconstruction of an inflationary universe in the context of one $f(\phi)T$ gravity, in which $T$ corresponds to the trace of energy momentum tensor is studied. To realize this reconstruction during the inflationary epoch, we consider…

General Relativity and Quantum Cosmology · Physics 2023-10-12 Ramon Herrera , Carlos Rios

We study slow-roll inflation and the generation of primordial fluctuations in $F(T)$ gravity's rainbow. We obtain the second order action for scalar and tensor perturbations and then calculate the primordial power spectrum for them. Thus,…

General Relativity and Quantum Cosmology · Physics 2022-02-18 Yoelsy Leyva , Carlos Leiva , Giovanni Otalora , Joel Saavedra

In the context of metric-affine gravity theories, where the metric and connection are independent, we examine actions involving quadratic terms in the Ricci scalar curvature and the Holst invariant. These actions are non-minimally coupled…

General Relativity and Quantum Cosmology · Physics 2025-06-17 Ioannis D. Gialamas , Kyriakos Tamvakis

The slow-roll approximation is an analytical approach to study dynamical properties of the inflationary universe. In this article, systematic construction of the slow-roll expansion for effective loop quantum cosmology is presented. The…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Joanna Luc , Jakub Mielczarek

We study a single fluid component in a flat like universe (FLU) governed by $f(T)$ gravity theories, where $T$ is the teleparallel torsion scalar. The FLU model, regardless the value of the spatial curvature $k$, identifies a special class…

High Energy Physics - Theory · Physics 2016-10-19 W. El Hanafy , G. G. L. Nashed

The $f(T)$ gravity is one of the extensions of teleparallel equivalent of general relativity, in which more general functions of the torsion scalar $T$ can be described. With the proposed functional form of $f(T) = \alpha T - \beta u^{-n} +…

General Relativity and Quantum Cosmology · Physics 2026-04-14 Suraj Kumar Behera , S. A. Kadam , Pratik P. Ray , B. Mishra

We examine the dynamics of inflation driven by multiple, interacting scalar fields and derive a multi field version of the Hubble slow roll expansion. We show that the properties of this expansion naturally generalize those of the single…

Astrophysics · Physics 2013-05-29 Richard Easther , John T Giblin

A Friedman cosmology is investigated based on scalar-tensor gravitation with general metric coupling and scalar potential functions. We show that for a broad class of such functions, the scalar field can be dynamically trapped using a…

General Relativity and Quantum Cosmology · Physics 2016-10-05 C. H. -T. Wang , J. A. Reid , A. St J. Murphy , D. Rodrigues , M. Al Alawi , R. Bingham , J. T. Mendonca , T. B. Davies

In this work, we explored warm inflation in the background of $f(R,T)$ gravity in the strong dissipation regime. Considering scalar field for FLRW universe, we derived modified field equations. We then deduced slow-roll parameters under…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Biswajit Deb , Sabina Yeasmin , Atri Deshamukhya

We construct models with the Gauss-Bonnet term multiplied to a function of the scalar field leading to inflationary scenario. The consideration is related with the slow-roll approximation. The cosmological attractor approach gives the…

General Relativity and Quantum Cosmology · Physics 2020-07-29 E. O. Pozdeeva

I describe a general approach to characterizing cosmological inflation outside the standard slow-roll approximation, based on the Hamilton-Jacobi formulation of scalar field dynamics. The basic idea is to view the equation of state of the…

High Energy Physics - Phenomenology · Physics 2016-08-24 William H. Kinney

In this study, we investigate the consequence of the constant-roll condition and examine the role of $f(Q,T)$ gravity in the cosmological inflation process. We analyze the inflationary scenario by calculating modified Friedmann equations,…

General Relativity and Quantum Cosmology · Physics 2023-01-11 K. El Bourakadi , M. Koussour , G. Otalora , M. Bennai , T. Ouali

We consider cosmological inflation generated by a scalar field slowly rolling off from a de Sitter maximum of its potential. The models belong to the class of hilltop models and represent the most general model of this kind in which the…

General Relativity and Quantum Cosmology · Physics 2016-09-05 Mariano Cadoni , Edgardo Franzin , Salvatore Mignemi

The study addresses matter-coupled modified gravity, particularly $f (T, \mathcal{T})$ gravity, unveiling distinct formalism. The research further discusses stability analysis, and the dynamical system approach, exploring the dynamics of…

General Relativity and Quantum Cosmology · Physics 2023-12-22 L. K. Duchaniya , Santosh V Lohakare , B. Mishra