English
Related papers

Related papers: Inflating without a flat potential: Viscous inflat…

200 papers

The Higgs field is an attractive candidate for the inflaton because it is an observationally confirmed fundamental scalar field. Importantly, it can be modeled by the most general renormalizable scalar potential. However, if the classical…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-29 Martin Bojowald , Suddhasattwa Brahma , Sean Crowe , Ding Ding , Joseph McCracken

We consider the inflation produced by two coupled fluids in the flat Friedmann-Robertson-Walker universe. Different cosmological models for describing inflation by use of an inhomogeneous equation of state for the fluid are investigated.…

General Relativity and Quantum Cosmology · Physics 2016-05-12 I. Brevik , A. V. Timoshkin

We consider supersymmetric inflation with the hybrid-type potential. In the absence of the symmetry that forbids Hubble-induced mass terms, the inflaton mass will be as large as the Hubble scale during inflation. We consider gravitational…

High Energy Physics - Phenomenology · Physics 2010-02-15 Tomohiro Matsuda

We construct non-linear inflaton potential energy densities that describe not-necessarily very-slowly-rolling closed and open inflation models, and compute tilted primordial spatial inhomogeneity power spectra that follow from quantum…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-02 Bharat Ratra

We propose to describe the acceleration of the universe by introducing a model of two coupled fluids. We focus on the accelerated expansion at the early stages. The inflationary expansion is described in terms of a van der Waals equation of…

General Relativity and Quantum Cosmology · Physics 2018-05-28 I. Brevik , V. V. Obukhov , A. V. Timoshkin

Inflation is nowadays a well-established paradigm consistent with all the observations. The precise nature of the inflaton is however unknown and its role could be played by any candidate able to imitate a scalar condensate in the slow-roll…

High Energy Physics - Phenomenology · Physics 2015-09-02 Javier Rubio

We study a warm inflationary model for different expansions assuming an anisotropic universe described by Bianchi I metric. The universe is filled with a scalar field or inflaton, radiation, and bulk viscous pressure. We carry out the…

General Relativity and Quantum Cosmology · Physics 2022-02-07 Mehdi Shokri , Jafar Sadeghi , Ramón Herrera , Saeed Noori Gashti

A model of inflation is proposed in which compact extra dimensions allow a graceful exit without recourse to flat potentials or super-Planckian field values. Though bubbles of true vacuum are too sparse to uniformly reheat the Universe by…

High Energy Physics - Theory · Physics 2008-12-18 Adam R. Brown

We study a recently proposed running kinetic inflation model in which the inflaton potential becomes flat due to rapid growth of the kinetic term at large inflaton field values. As concrete examples, we build a variety of chaotic inflation…

High Energy Physics - Phenomenology · Physics 2010-12-09 Kazunori Nakayama , Fuminobu Takahashi

Several models of inflection point inflation with the volume modulus as the inflaton are investigated. Non-perturbative superpotentials containing two gaugino condensation terms or one such term with threshold corrections are considered. It…

High Energy Physics - Theory · Physics 2009-02-10 Marcin Badziak , Marek Olechowski

We propose a model for cosmic inflation which is based on an effective description of strongly interacting, nonsupersymmetric matter within the framework of dynamical Abelian projection and centerization. The underlying gauge symmetry is…

High Energy Physics - Phenomenology · Physics 2009-11-07 Ralf Hofmann , Mathias Th. Keil

One common approach for cosmic inflation consists in couple Einstein's gravity with a scalar field, often referred to inflaton field. In order to derive analytic simple scenarios, we usually work in the {\it slow-roll} regime. In such an…

General Relativity and Quantum Cosmology · Physics 2021-01-01 J. R. L. Santos , P. H. R. S. Moraes

The decay of the inflaton into radiation and particles during the slow-roll suggests that these may interact with each other and that the latter may also decay into subproducts before inflation is completed. As a consequence, the fluid is…

Astrophysics · Physics 2007-05-23 Jose Pedro Mimoso , Ana Nunes , Diego Pavon

In constant-roll inflation, the scalar field that drives the accelerated expansion of the Universe is rolling down its potential at a constant rate. Within this framework, we highlight the relations between the Hubble slow-roll parameters…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-08 Alexandros Karam , Luca Marzola , Thomas Pappas , Antonio Racioppi , Kyriakos Tamvakis

We consider a simple inflation model with a complex scalar field coupled to gravity non-minimally. Both the modulus and the angular directions of the complex scalar are slowly rolling, leading to two-field inflation. The modulus direction…

High Energy Physics - Phenomenology · Physics 2015-05-28 Jinn-Ouk Gong , Hyun Min Lee

Slow-roll inflation generically makes several predictions: a flat Universe, primordial adiabatic density perturbations, and a stochastic gravity-wave background. Each inflation model will further predict specific relations between the…

Astrophysics · Physics 2007-05-23 Marc Kamionkowski

Slow-roll inflation requires the inflaton field to have an exceptionally flat potential, which combined with measurements of the scale of inflation demands some degree of fine-tuning. Alternatively, the flatness of the potential could be…

High Energy Physics - Phenomenology · Physics 2015-06-23 Djuna Croon , Veronica Sanz

We propose a possibility that the inflaton potential is significantly modified after inflation due to heavy field dynamics. During inflation there may be a heavy scalar field stabilized at a value deviated from the low-energy minimum. As…

High Energy Physics - Phenomenology · Physics 2016-02-24 Naoya Kitajima , Fuminobu Takahashi

We present an effective model where the inflaton is a relaxion that scans the Higgs mass and sets it at the weak scale. The dynamics consist of a long epoch in which inflation is due to the shallow slope of the potential, followed by a few…

High Energy Physics - Phenomenology · Physics 2017-06-05 Walter Tangarife , Kohsaku Tobioka , Lorenzo Ubaldi , Tomer Volansky

We investigate the effects of large inhomogeneities in both the inflaton field and its momentum. We find that in general, large kinetic perturbations reduce the number of e-folds of inflation. In particular, we observe that inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-13 Matthew Elley , Josu C. Aurrekoetxea , Katy Clough , Raphael Flauger , Panagiotis Giannadakis , Eugene A. Lim