English
Related papers

Related papers: Warm inflation in Horndeski gravity

200 papers

We study the cosmological inflation and reheating in a teleparallel model of gravity. Reheating is assumed to be due to the decay of a scalar field to radiation during its rapid oscillation. By using cosmological perturbations during…

General Physics · Physics 2019-07-26 P. Goodarzi , H. Mohseni Sadjadi

In this work, we investigate the preheating mechanism after inflation in general scalar-tensor theories of gravity. In the present scenario, we consider two-field scenario and then derive the potential of exponential and hyperbolic tangent…

General Relativity and Quantum Cosmology · Physics 2023-05-10 Peeravit Koad , Jatechan Channuie , Phongpichit Channuie

The scenario of the slow-roll inflation is studied in the frame of the scalar-tensor theory of gravity where the scalar field has a non-minimal coupling to the geometric part. After deriving the main dynamical and perturbation equations,…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Abolhassan Mohammadi , Tayeb Golanbari , Jamil Enayati , Shahram Jalalzadeh , Khaled Saaidi

Recently, it was proposed that a small true vacuum universe can inflate spontaneously, in principle. Furthermore, there should be matter creation in vacuum inflation due to quantum fluctuations, and the matter created will influence the…

General Relativity and Quantum Cosmology · Physics 2017-05-01 Zhiqiang Huang , Dongfeng Gao , Qing-yu Cai

We discuss and expand a new approach to the thermodynamics of scalar-tensor gravity and its diffusion toward general relativity (seen as an equilibrium state) proposed in a previous Letter [Phys. Rev. D 103, L121501 (2021)], upon which we…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Valerio Faraoni , Andrea Giusti , Andrea Mentrelli

A warm intermediate inflationary model in the context of Generalized Chaplygin Gas is investigated. We study this model in the weak and strong dissipative regimes, considering a generalized form of the dissipative coefficient…

General Relativity and Quantum Cosmology · Physics 2016-02-17 Ramón Herrera , Nelson Videla , Marco Olivares

Power-Law inflation with scale factor $a \propto t^m$ is investigated in the context of warm inflation. The treatment is performed in the weak and strong dissipation limits. In addition, we discuss the three common cases for the thermal…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-12 M. Alhallak , N. Chamoun , M. S. Eldaher

Warm inflation is an inflationary scenario in which a thermal bath coexists with the inflaton during inflation. This is unlike standard cold inflation in which the Universe is effectively devoid of particles during inflation. The thermal…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-10 Raghavan Rangarajan

Thermal inflation, a brief low energy inflation after the primordial inflation, resolves the moduli problem in the context of supersymmetric cosmology. In the thermal inflation scenario, the primordial power spectrum is modestly redshifted…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-14 Heeseung Zoe

We propose a scenario that can explain the early-time inflation and the late-time dark energy within a unified framework. A scalar potential combining power-law and exponential type in a context of extended Jordan-Brans-Dicke gravity is…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-15 Kunio Kaneta , Kin-ya Oda , Motohiko Yoshimura

Within the framework of the scalar-tensor theory we consider a hill-climbing inflation, in which the effective Planck mass increases in time. We obtain the Einstein frame potential with infinitely long and flat plateau as we approach…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-19 Michal Artymowski , Zygmunt Lalak , Kin-Ya Oda

Ideas borrowed from renormalization group are applied to warm inflation to characterize the inflationary epoch in terms of flows away from the de Sitter regime. In this framework different models of inflation fall into universality classes.…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-03 Arjun Berera , Joel Mabillard , Mauro Pieroni , Rudnei O. Ramos

We revisit the old (fourth-order or quadratically generated) gravity model of Starobinsky in four space-time dimensions, and derive the (inflaton) scalar potential in the equivalent scalar-tensor gravity model via a Legendre-Weyl transform.…

High Energy Physics - Theory · Physics 2010-12-09 S. Kaneda , S. V. Ketov , N. Watanabe

The recently suggested generalized unimodular gravity theory, which was originally put forward as a model of dark energy, can serve as a model of cosmological inflation driven by the effective perfect fluid -- the dark purely gravitational…

General Relativity and Quantum Cosmology · Physics 2019-12-11 A. O. Barvinsky , N. Kolganov

Using Hamilton-Jacobi formalism, The scenario of warm inflation with viscous pressure is considered. The formalism gives a way of computing the slow-rolling parameters without extra approximation, and it is well-known as a powerful method…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-17 L. Akhtari , A. Mohammadi , K. Sayar , Kh. Saaidi

In warm inflation, dissipation due to the interactions of the inflaton field to other light degrees of freedom leads naturally to the enhancement of the primordial spectrum during the last 10-20 efolds of inflation. We study this effect in…

High Energy Physics - Phenomenology · Physics 2022-01-05 Mar Bastero-Gil , Marta Subías Díaz-Blanco

We discuss the spectrum of scalar density perturbations from warm inflation when the friction coefficient $\Gamma$ in the inflaton equation is dependent on the inflaton field. The spectral index of scalar fluctuations depends on a new…

Astrophysics · Physics 2009-11-10 Lisa M. H. Hall , Ian G. Moss , Arjun Berera

This thesis compiles the results of six works which deal with - inflationary model building and estimation of cosmological parameters from various field theoretic setup, quantification of reheating temperature, studies of leptogenesis in…

High Energy Physics - Theory · Physics 2016-04-12 Sayantan Choudhury

The model of RH neutrino fields coupled to the MSSM is shown to yield a large parameter regime of warm inflation. In the strong dissipative regime, it is shown that inflation, driven by a single sneutrino field, occurs with {\it all field…

High Energy Physics - Phenomenology · Physics 2011-08-17 Mar Bastero-Gil , Arjun Berera

Anisotropic inflation is a model succeeded in explaining statistical anisotropy. Warm inflation is a model succeeded in providing a mechanism of reheating during inflation. We study anisotropic warm inflation focusing on the cosmic no-hair…

High Energy Physics - Theory · Physics 2023-06-09 Sugumi Kanno , Ann Mukuno , Jiro Soda , Kazushige Ueda