English
Related papers

Related papers: G-Warm inflation: Intermediate model

200 papers

We consider warm inflation in the context of holographic cosmology. The weak and the strong dissipative regime are analysed in the slow-roll approximation and within what is known as intermediate inflation. For an appropriate choice of the…

High Energy Physics - Theory · Physics 2022-03-11 Zahra Bouabdallaoui , Ahmed Errahmani , Mariam Bouhmadi-López , Taoufik Ouali

We analyze the dynamics of inflationary models with a coupling of the inflaton $\phi$ to gauge fields of the form $\phi F \tilde{F}/f$, as in the case of axions. It is known that this leads to an instability, with exponential amplification…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-16 Ricardo Z. Ferreira , Alessio Notari

Warm inflationary universe models in the context of logamediate expansion are studied. General conditions required for these models to be realizable and discussed. This study is done in the weak and strong dissipative regimes. The…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Ramon Herrera , Marco Olivares

Conditions are obtained for the existence of a warm inflationary attractor in the system of equations describing an inflaton coupled to radiation. These conditions restrict the temperature dependence of the dissipative terms and the size of…

Astrophysics · Physics 2011-07-13 Ian G Moss , Chun Xiong

Inflation, as currently understood, requires the presence of fields with very flat potentials. Supersymmetric models in which supersymmetry breaking is communicated by supergravity naturally yield such fields, but the scales are typically…

High Energy Physics - Phenomenology · Physics 2009-10-30 Michael Dine , Antonio Riotto

We investigate warm inflationary scenario in which the accelerated expansion of the early Universe is driven by chameleon-like scalar fields. Due to the non-minimal coupling between the scalar field and the matter sector, the…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Haidar Sheikhahmadi , Abolhassan Mohammadi , Ali Aghamohammadi , Tiberiu Harko , Ramón Herrera , Christian Corda , Amare Abebe , Khaled Saaidi

Departing from standard slow-roll conditions is one way of putting the inflationary paradigm to test, and constraining the dynamics of the inflaton field with a constant-rate of roll of the inflaton field, a.k.a. the constant-roll scenario,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-19 Sandip Biswas , Kaushik Bhattacharya , Suratna Das

This paper explores the dynamics of warm intermediate and logamediate inflationary models during weak dissipative regime with a general form of dissipative coefficient. We analyze these models within the framework of locally rotationally…

General Relativity and Quantum Cosmology · Physics 2016-03-23 M. Sharif , Rabia Saleem

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

A first order inflation model where a gauge coupling constant runs as the universe inflates is investigated. This model can solve the graceful-exit problem within Einstein gravity by varying the bubble formation rate. The sufficient…

High Energy Physics - Phenomenology · Physics 2008-02-03 Jae-weon Lee , In-guy Koh

In the present paper we study warm inflationary universe models in the context of a polytropic gas. We derive the characteristics of this model in slow-roll approximation and develop our model in two cases, 1- For a constant dissipative…

General Relativity and Quantum Cosmology · Physics 2015-06-16 M. R. Setare , M. J. S. Houndjo , V. Kamali

We study inflationary models in which the effective potential of the inflaton field does not have a minimum, but rather gradually decreases at large $\phi$. In such models the inflaton field does not oscillate after inflation, and its…

High Energy Physics - Phenomenology · Physics 2009-09-29 Gary Felder , Lev Kofman , Andrei Linde

A safe way to reheat the universe, in models of natural and quadratic inflation, is through shift symmetric couplings between the inflaton $\phi$ and the Standard Model (SM), since they do not generate loop corrections to the potential…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Ricardo Z. Ferreira , Alessio Notari

Warm inflationary universe models in the context of a Chaplygin gas equation are studied. General conditions required for these models to be realizable are derived and discussed. By using a chaotic potential we develop models for a…

Astrophysics · Physics 2008-12-18 Sergio del Campo , Ramon Herrera

A new modified string-inspired modular invariant supergravity model is proposed and is applied to realize the slow roll inflation in Einstein frame. Because inflation deals with Planck scale physics, the dilaton can be a strong candidate…

High Energy Physics - Phenomenology · Physics 2011-04-22 Mitsuo J. Hayashi , Yuta Koshimizu , Toyokazu Fukuoka , Kenji Takagi , Hikoya Kasari

Assuming a first order phase transition during inflation, a model scenario is described which does not require a tiny coupling constant. Thermal equilibrium is closely maintained as inflation commences. No large scale reheating is…

Astrophysics · Physics 2008-11-26 Arjun Berera

We propose and investigate a general form of the dissipative coefficient $\Gamma=C_{\phi}T^{m}/\phi^{m-1}$ in warm inflation. We focus on discussing the strong dissipative processes $r=\Gamma/3H\gg1$ in the thermal state of approximate…

High Energy Physics - Phenomenology · Physics 2010-04-15 Yi Zhang

The reconstruction of an inflationary universe in the context of the Galileon model or G-model, considering as attractors the scalar spectral index $n_S(N)$ and the tensor to scalar ratio $r(N)$ as a function of the number of e-folding $N$…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Ramon Herrera

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

We explore the homogeneous background dynamics and the evolution of generated perturbations of cosmological inflation that is driven by multiple scalar fields interacting with a perfect fluid.Then we apply the method to warm inflation…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Yang-Yang Wang , Jian-Yang Zhu , Xiao-Min Zhang