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Related papers: $f(\phi) R$-models for inflation

200 papers

Although natural inflation is a theoretically well-motivated model for cosmic inflation, it is in tension with recent Planck cosmic microwave background anisotropy measurements. We present a way to alleviate this tension by considering a…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-25 Yakefu Reyimuaji , Xinyi Zhang

Models of inflation in which the Higgs field is non-minimally coupled to gravity lead, after a recaling of the metric, to a complicated expression for the potential of the inflaton field. Nevertheless, this potential produces the desired…

High Energy Physics - Theory · Physics 2022-06-08 Noureddine Mohammedi

We investigate a class of inflationary models in modified gravity theories which contain a non-minimal coupling between gravity and a scalar field $\phi$ (inflaton) as $f(R,T)=R \bigl(1+\alpha+ \kappa^4 \beta T \bigr)+\kappa^2\gamma T $…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Payel Sarkar , Ashmita , Prasanta Kumar Das

We propose an inflationary scenario, M-flation, in which inflation is driven by three $N\times N$ hermitian matrices $\Phi_i, i=1,2,3$. The inflation potential of our model, which is strongly motivated from string theory, is constructed…

High Energy Physics - Theory · Physics 2010-10-13 Amjad Ashoorioon , Hassan Firouzjahi , M. M. Sheikh-Jabbari

In this work we shall study a class of $f(R,\phi)$ gravity models which during the inflationary era, which is the large curvature regime, result to an effective inflationary Lagrangian that contains a rescaled Einstein-Hilbert term $\alpha…

General Relativity and Quantum Cosmology · Physics 2022-03-14 V. K. Oikonomou , Ifigeneia Giannakoudi , Achilles Gitsis , Konstantinos-Rafail Revis

We study a model of inflation in which a scalar field $\chi$ is non-minimally coupled to Starobinsky's $R^2$ gravity. After transforming it to the Einstein frame, a new scalar field, the scalaron $\phi$, will appear and couple to $\chi$…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-21 Shi Pi , Ying-li Zhang , Qing-Guo Huang , Misao Sasaki

In the context of nonminimally coupled $f(R)$ gravity theories, we study early inflation driven by a nonlinear monopole magnetic field which is nonminimally coupled to curvature. In order to isolate the effects of the nonminimal coupling…

General Relativity and Quantum Cosmology · Physics 2018-06-05 Giovanni Otalora , Ali Övgün , Joel Saavedra , Nelson Videla

We describe a way to construct supergravity models with an arbitrary inflaton potential V ({\phi}) and show that all other scalar fields in this class of models can be stabilized at the inflationary trajectory by a proper choice of the…

High Energy Physics - Theory · Physics 2011-02-18 Renata Kallosh , Andrei Linde , Tomas Rube

A field kinetic coupling with the Einstein tensor leads to a gravitationally enhanced friction during inflation, by which even steep potentials with theoretically natural model parameters can drive cosmic acceleration. In the presence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Shinji Tsujikawa

In this work, we investigated several inflationary scenarios within the framework of modified $f(Q,\phi)$ gravity with a nonminimal coupling between the scalar field and the nonmetricity scalar. We focused on the impact of the coupling…

General Relativity and Quantum Cosmology · Physics 2026-04-30 F. Mavoa , M. B. Barry , R. Ndioukane , M. G. Ganiou , F. K. Ahloui

In this short note we discuss the possibility of producing a slow rolling inflationary background by considering a massive scalar field whose kinetic term is non-minimally coupled to gravity.

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Cristiano Germani , Alex Kehagias

In this paper, we investigate chaotic inflation from scalar field subjected to potential in the framework of $f(R^2, P, Q)$-gravity, where we add a correction to Einstein's gravity based on a function of the square of the Ricci scalar…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Shynaray Myrzakul , Ratbay Myrzakulov , Lorenzo Sebastiani

Theories where the Planck scale is dynamically generated from dimensionless interactions provide predictive inflationary potentials and super-Planckian field variations. We first study the minimal single-field realisation in the low-energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-28 Kristjan Kannike , Gert Hütsi , Liberato Pizza , Antonio Racioppi , Martti Raidal , Alberto Salvio , Alessandro Strumia

We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Shinji Tsujikawa , Junko Ohashi , Sachiko Kuroyanagi , Antonio De Felice

We explore inflationary cosmology in a theory where there are two scalar fields which non-minimally couple to the Ricci scalar and an additional $R^2$ term, which breaks the conformal invariance. Particularly, we investigate the slow-roll…

High Energy Physics - Theory · Physics 2015-07-10 Kazuharu Bamba , Sergei D. Odintsov , Petr V. Tretyakov

We present a supergravity inflationary scenario in which the inflaton field takes values considerably larger than the Planck scale. It is based on a class of inflationary potentials which can be derived from ``singular'' Kaehler potentials…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. Panagiotakopoulos

Inflation models are compared with observation on the assumption that the curvature perturbation is generated from the vacuum fluctuation of the inflaton field. The focus is on single-field models with canonical kinetic terms, classified as…

High Energy Physics - Theory · Physics 2009-04-22 D H Lyth

We provide an update on five relatively well motivated inflationary models in which the inflaton is a Standard Model singlet scalar field. These include i) the textbook quadratic and quartic potential models but with additional couplings of…

High Energy Physics - Phenomenology · Physics 2016-04-28 Nobuchika Okada , Vedat Nefer Şenoğuz , Qaisar Shafi

We consider "new inflation" inflationary models at small fields, embedded in minimal ${\cal N}=1$ supergravity with a single chiral superfield. Imposing a period of inflation compatible with experiment severely restricts possible models,…

High Energy Physics - Theory · Physics 2016-10-12 Heliudson Bernardo , Horatiu Nastase

The exact solutions in the standard inflationary model based on the self-interacting scalar field minimally coupled to gravity are considered. The shape's freedom of the self-interacting potential $V(\phi)$ is postulated to obtain a new set…

General Relativity and Quantum Cosmology · Physics 2009-10-30 S. V. Chervon , V. M. Zhuravlev , V. K. Shchigolev