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Related papers: On Perturbations in Warm Inflation

200 papers

Inflationary cosmology proposes that the early Universe undergoes accelerated expansion, driven, in simple scenarios, by a single scalar field, or inflaton. The form of the inflaton potential determines the initial spectra of density…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-21 Richard Easther , Benedict Bahr-Kalus , David Parkinson

We introduce warm quintessential inflation and study it in the weak dissipative regime. We consider the original quintessential inflation model, which approximates quartic chaotic inflation at early times and thawing quartic…

General Relativity and Quantum Cosmology · Physics 2019-07-17 Konstantinos Dimopoulos , Leonora Donaldson-Wood

We speculate that the early Universe was inside a primordial black hole. The interior of the the black hole is a dS background and the two spacetimes are separated on the surface of black hole's event horizon. We argue that this picture…

High Energy Physics - Theory · Physics 2016-10-13 Hassan Firouzjahi

Observations of the temperature anisotropies in the Cosmic Microwave Background (CMB) radiation show that the models of inflation with the monomial potentials are inconsistent with the allowed $n_s-r$ bounds. However certain monomial…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-17 Richa Arya , Raghavan Rangarajan

We show that models of `just enough' inflation, where the slow-roll evolution lasted only $50-60$ e-foldings, feature modifications of the CMB power spectrum at large angular scales. We perform a systematic and model-independent analysis of…

High Energy Physics - Theory · Physics 2015-06-22 Michele Cicoli , Sean Downes , Bhaskar Dutta , Francisco G. Pedro , Alexander Westphal

Using the fact that we only observe those modes which exit the Hubble horizon during inflation, one can calculate the entanglement entropy of such long-wavelength perturbations by tracing out unobservable sub-Hubble fluctuations they are…

High Energy Physics - Theory · Physics 2022-06-14 Suddhasattwa Brahma

We analyze the onset of inflation for a simple single-field model when the system begins with significant inhomogeneities on length-scales shorter than the initial Hubble radius. We incorporate certain nonlinear interactions among the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-17 Jolyon K. Bloomfield , Patrick Fitzpatrick , Kiriakos Hilbert , David I. Kaiser

The statistical properties of the primordial density perturbations has been considered in the past decade as a powerful probe of the physical processes taking place in the early universe. Within the inflationary paradigm, the properties of…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Gabriel Leon , Daniel Sudarsky

This article discusses density perturbations in inflationary models, offering a pedagogical description of how these perturbations are generated by quantum fluctuations in the early universe. A key feature of inflation is that that rapid…

High Energy Physics - Theory · Physics 2014-01-15 Alan H. Guth

From a model-building perspective, the inflationary sector might very well have no direct couplings to other species, apart from inevitable gravitational interactions. Within the context of General Relativity, a thermal universe can still…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-11 Daniel G. Figueroa , Erwin H. Tanin

The fluctuations in the inflaton field at the end of inflation which seed the density perturbations are prepared in a pure quantum state. It is generally assumed that some physics causes this pure state to decohere so that it should be…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jonathan W. Sharman , Guy D. Moore

In this work, we study the warm inflation mechanism in the presence of the Barrow holographic dark energy model. Warm inflation differs from other forms of inflation primarily in that it assumes that radiation and inflaton fields exist and…

General Relativity and Quantum Cosmology · Physics 2025-05-13 Moli Ghosh , Prabir Rudra , Surajit Chattopadhyay , Behnam Pourhassan

We propose an inflationary primordial feature model that can explain both the large and small-scale anomalies in the currently measured cosmic microwave background (CMB) anisotropy spectra, revealing a clip of adventurous history of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-15 Matteo Braglia , Xingang Chen , Dhiraj Kumar Hazra

This paper is devoted to study the warm inflation using vector fields in the background of locally rotationally symmetric Bianchi type I universe model. We formulate the field equations, slow-roll and perturbation parameters (scalar and…

General Relativity and Quantum Cosmology · Physics 2015-06-18 M. Sharif , Rabia Saleem

In this study, we investigate the full nonlinear dynamics of warm inflation driven by the quartic inflaton potential, avoiding any simplifying approximations. The thermal backreaction is incorporated through a dissipation coefficient that…

General Relativity and Quantum Cosmology · Physics 2025-11-20 Bhargabi Saha , Malay K. Nandy

We present a model where the inflaton field behaves like quintessence at late times, generating the present phase of accelerated expansion. This is achieved within the framework of warm inflation, in particular the Warm Little Inflaton…

High Energy Physics - Phenomenology · Physics 2019-10-23 João G. Rosa , Luís B. Ventura

We discuss how dissipative effects and the presence of a thermal radiation bath, which are inherent characteristics of the warm inflation dynamics, can evade the recently proposed Swampland conjectures. Different forms of dissipation terms,…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-18 Meysam Motaharfar , Vahid Kamali , Rudnei O. Ramos

This thesis is dedicated to analysing the generation and destruction of quantum correlations in the context of inflationary cosmology and an experiment of 'analogue' preheating. Inflation is a phase of accelerated expansion of the Universe,…

General Relativity and Quantum Cosmology · Physics 2024-12-04 Amaury Micheli

We analyze various phases of inflation based on the anomaly-induced effective action of gravity (modified Starobinsky model), taking the cosmological constant Lambda and k=0, +/- 1 topologies into account. The total number of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. M. Pelinson , I. L. Shapiro , F. I. Takakura

There exists the "entropy problem" of the early universe, that is, why did the universe begin with an extremely low entropy and how did it evolve into such high entropy at late times? It has been long believed that inflation cannot be the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-12 Pisin Chen , Po-Shen Hsin , Yuezhen Niu
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