English
Related papers

Related papers: New slow-roll approximations for inflation in Eins…

200 papers

In this paper, we investigate hypergeometric stringy corrections in the swampland program for rescaled gravity. Precisely, we study inflationary models from Gauss-Bonnet hypergeometric scalar couplings via the falsification scenario. We…

High Energy Physics - Theory · Physics 2024-07-02 Saad Eddine Baddis , Adil Belhaj

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

In presence of Gauss-Bonnet corrections, we study anisotropic inflation aided by a massless $SU(2)$ gauge field where both the gauge field and the Gauss-Bonnet term are non-minimally coupled to the inflaton. In this scenario, under…

High Energy Physics - Theory · Physics 2017-01-18 Sayantani Lahiri

We examine the role of using symmetry and effective field theory in inflationary model building. We describe the standard formulation of starting with an approximate shift symmetry for a scalar field, and then introducing corrections…

High Energy Physics - Theory · Physics 2015-07-29 Mark P. Hertzberg

In this paper we consider the $\alpha-$attractor model and study inflation under a non-slow-roll dynamics. More precisely, we follow the approach recently proposed by Gong and Sasaki \cite{Gong:2015ypa} by means of assuming…

General Relativity and Quantum Cosmology · Physics 2016-04-05 K. Sravan Kumar , João Marto , Paulo Vargas Moniz , Suratna Das

We consider a single scalar field inflation model with Higgs potential and curvature corrections given by non-minimal derivative coupling to gravity and coupling to the Gauss-Bonnet invariant. Exact analytical expressions, within the…

General Relativity and Quantum Cosmology · Physics 2019-10-25 L. N. Granda , D. F. Jimenez

We show that a non-minimal coupling to gravity can not only make some inflationary models consistent with cosmological data, similar to the case of Higgs inflation, but can also invoke slow-roll violation to realize graceful exit from…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-09 Tomo Takahashi , Tommi Tenkanen , Shuichiro Yokoyama

We present a new approximation scheme that allows us to increase the accuracy of analytical predictions of the power spectra of inflationary perturbations for two specific classes of inflationary models. Among these models are chaotic…

Astrophysics · Physics 2015-06-24 C. A. Terrero-Escalante , D. J. Schwarz , A. A. Garcia

In this paper we revisit the relationship between the Einstein--Friedman and the Abel equations to demonstrate how it might be applied to the inflationary analysis in a flat Friedman universe filled with a real-valued scalar field. The…

General Relativity and Quantum Cosmology · Physics 2019-07-30 Anna V. Yaparova , Artyom V. Yurov , Valerian A. Yurov

In this work, we examine cosmological constraints on models of composite inflation based on the slow-roll approximation by using the recent Planck measurement. We compare the spectral index of curvature perturbation (and its running) and…

High Energy Physics - Phenomenology · Physics 2016-06-30 Phongpichit Channuie

Slow roll reconstruction is derived from the Hamilton-Jacobi formulation of inflationary dynamics. It automatically includes information from sub-leading terms in slow roll, and facilitatesthe inclusion of priors based on the duration on…

Astrophysics · Physics 2009-06-23 Peter Adshead , Richard Easther

In this note we point out that, contrary to the standard point of view, slow roll inflation is due to high gravitational friction. We show that the requirement of slow roll coincides with the requirement of a flat scalar field potential in…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-07 Cristiano Germani

We compare the standard single scalar field inflationary predictions with those of an inflationary phase driven by a tachyon field. A slow-roll formalism is defined for tachyon inflation and we derive the spectra of scalar and tensor…

Astrophysics · Physics 2016-11-09 Filippo Vernizzi , Daniele Steer

We study the dynamics of inflation in a generalized scalar-torsion gravity scenario by assuming a canonical scalar field non-minimally coupled to torsion with a Galileon-type self-interaction. After obtaining the field equations for a flat…

General Relativity and Quantum Cosmology · Physics 2019-08-26 Manuel Gonzalez-Espinoza , Giovanni Otalora , Nelson Videla , Joel Saavedra

Slow-roll inflation is studied in theories where the inflaton field is conformally coupled to the Ricci scalar. In particular, the case of Higgs field inflation in the context of the noncommutative spectral action is analyzed. It is shown…

High Energy Physics - Theory · Physics 2010-08-31 Michel Buck , Malcolm Fairbairn , Mairi Sakellariadou

A new supergravity D-term, not associated to gauged R-symmetry, was recently discovered and used to construct new supergravity models. In this paper we use a generalization of the new D-term that we used in previous works, to construct a…

High Energy Physics - Theory · Physics 2022-08-29 Hun Jang , Massimo Porrati

The aim of this paper is to explore warm inflation in the background of $f(\mathcal{G})$ theory of gravity using scalar fields for the FRW universe model. We construct the field equations under slow-roll approximations and evaluate the…

General Relativity and Quantum Cosmology · Physics 2016-09-21 M. Sharif , Ayesha Ikram

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

A new model for inflation using modified gravity in the Palatini formalism is constructed. Here non-minimal coupling of scalar field h with the curvature R as a general function f(R,h) is considered. Explicit inflation models for some…

General Relativity and Quantum Cosmology · Physics 2021-05-19 Nayan Das , Sukanta Panda

We study inflation induced by (power-low) scalar curvature corrections to General Relativity. The class of inflationary scalar potentials $V(\sigma)\sim\exp[n\,\sigma]$, $n$ general parameter, is investigated in the Einsein frame and the…

General Relativity and Quantum Cosmology · Physics 2014-09-22 L. Sebastiani , G. Cognola , R. Myrzakulov , S. D. Odintsov , S. Zerbini