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Related papers: Constant-roll Inflation in $f(T)$ Teleparallel Gra…

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In the last dozen years a wide and variegated mass of observational data revealed that the universe is now expanding at an accelerated rate. In the absence of a well-based theory to interpret the observations, cosmography provides…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Ester Piedipalumbo , Enrica Della Moglie , Roberto Cianci

The previously introduced class of two-parametric phenomenological inflationary models in General Relativity in which the slow-roll assumption is replaced by the more general, constant-roll condition is generalized to the case of $f(R)$…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-15 Hayato Motohashi , Alexei A. Starobinsky

In this work, we study a constant-roll inflationary model in the Palatini formalism using modified gravity. Here our action consists a non-minimal coupling of a scalar field $\phi$ with Ricci scalar $R$ in a general form of $f(R,\phi)$.…

General Relativity and Quantum Cosmology · Physics 2023-04-19 Sukanta Panda , Arun Rana , Rahul Thakur

We present a tachyonic field inflationary model in a teleparallel framework. We show that tachyonic coupled with the f(T) gravity model can describe the inflation era in which f(T) is an arbitrary function of torsion scalar T. For this…

General Relativity and Quantum Cosmology · Physics 2020-02-24 Amin Rezaei Akbarieh , Yousef Izadi

In recent years, modifications to General Relativity (GR) have been explored to address cosmological observations, particularly in the context of late-time cosmic acceleration. Among these, modifications based on the Teleparallel Equivalent…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-29 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak

We study logamediate inflation in the context of $f(T)$ teleparallel gravity. $f(T)$-gravity is a generalization of the teleparallel gravity which is formulated on the Weitzenb\"{o}ck spacetime, characterized by the vanishing curvature…

General Relativity and Quantum Cosmology · Physics 2017-02-28 Kazem Rezazadeh , Asrin Abdolmaleki , Kayoomars Karami

We derive an exact $f(T)$ gravity in the absence of ordinary matter in Friedmann-Robertson-Walker (FRW) universe, where $T$ is the teleparallel torsion scalar. We show that vanishing of the energy-momentum tensor $\mathcal{T}^{\mu \nu}$ of…

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

Cosmological inflation remains a key paradigm for explaining the earliest stages of the Universe, yet the theoretical limitations of General Relativity (GR) motivate the development of alternative formulations capable of addressing both…

General Relativity and Quantum Cosmology · Physics 2025-11-13 Maryam Shiravand , Saeed Fakhry , Javad T. Firouzjaee , Ali Tizfahm

The previously proposed class of phenomenological inflationary models in which the assumption of inflaton slow-roll is replaced by the more general, constant-roll condition is compared with the most recent cosmological observational data,…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-28 Hayato Motohashi , Alexei A. Starobinsky

Teleparallel gravity offers a new avenue in which to construct gravitational models beyond general relativity. While teleparallel gravity can be framed in a way to be dynamically equivalent to general relativity, its modifications are…

General Relativity and Quantum Cosmology · Physics 2021-01-28 Sebastian Bahamonde , Viktor Gakis , Stella Kiorpelidi , Tomi Koivisto , Jackson Levi Said , Emmanuel N. Saridakis

The scenario of constant-roll inflation is studied where the inflaton is a scalar field with modified kinetic term, known as non-canonical scalar field. This modification leads to some changes in the slow-roll parameters, and also by taking…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Abolhassan Mohammadi , Khaled Saaidi , Haidar Sheikhahmadi

We investigate a bounce inflation model with a graceful exit into the Friedmann-Robertson-Walker (FRW) decelerated Universe within $f(T)$ gravity framework, where $T$ is the torsion scalar in the teleparallelism. We study the cosmic thermal…

General Relativity and Quantum Cosmology · Physics 2016-10-13 Kazuharu Bamba , G. G. L. Nashed , W. El Hanafy , Sh. K. Ibraheem

In this work, we extend the bottom-up reconstruction framework of $F(R)$ gravity to other modified gravities, and in particular for $f(\phi)R$ and mimetic $F(R)$ gravities. We investigate which are the important conditions in order for the…

General Relativity and Quantum Cosmology · Physics 2018-03-14 S. D. Odintsov , V. K. Oikonomou

We study warm inflation in the framework of $f(\phi)T$ gravity, where $\phi$ is the inflaton and $T$ is the trace of the energy-momentum tensor. The inflaton field is assumed to roll on the natural potential and the result is analyzed in…

General Relativity and Quantum Cosmology · Physics 2024-08-02 Sabina Yeasmin , Atri Deshamukhya

Generalised Teleparallel gravity, also referred to as f(T) gravity, has been recently proposed as an extended theory of gravitation able to give rise to an accelerated expansion in a matter only universe. The cosmic speed up is driven by an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Vincenzo F. Cardone , Ninfa Radicella , Stefano Camera

In this paper we shall consider an exponential inflationary model in the context of vacuum $F(R)$ gravity. By using well-known reconstruction techniques, we shall investigate which $F(R)$ gravity can realize the exponential inflation…

General Relativity and Quantum Cosmology · Physics 2018-03-14 V. K. Oikonomou

Teleparallel gravity is a modified theory of gravity in which the Ricci scalar $R$ of the Lagrangian replaced by the general function of torsion scalar $T$ in action. With that, cosmology in teleparallel gravity becomes profoundly…

General Physics · Physics 2020-09-09 Sanjay Mandal , P. K. Sahoo

This work investigates the dynamical evolution of the universe within the framework of symmetric teleparallel $f(Q,\mathcal{T})$ gravity, where $Q$ is the non-metricity scalar and $\mathcal{T}$ is the trace of the energy-momentum tensor. We…

General Relativity and Quantum Cosmology · Physics 2026-05-19 S. H. Shekh , S. B. Thool , Pankaj Kumar , P. C. Kalan , R. M. Dhaigude

In this work, we study constant-roll inflation driven by a scalar field with non-minimal derivative coupling to gravity, via the Einstein tensor. This model contains a free parameter, $\eta$, which quantifies the non-minimal derivative…

General Relativity and Quantum Cosmology · Physics 2019-10-23 A. Oliveros , Hernán E. Noriega

We study cosmological solutions in nonlocal teleparallel gravity or $f(T)$ theory, where $T$ is the torsion scalar in teleparallel gravity. This is a natural extenstion of the usual teleparallel gravity with nonlocal terms. In this work the…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Kazuharu Bamba , Davood Momeni , Mudhahir Al Ajmi