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We investigate theoretical and observational aspects of a warm inflation scenario driven by the $\beta$-exponential potential, which generalizes the well-known power law inflation. In such a scenario, the decay of the inflaton field into…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-02 F. B. M. dos Santos , R. Silva , S. Santos da Costa , M. Benetti , J. S. Alcaniz

After cosmic inflation and before the transition to radiation domination, the cosmic energy density may have been dominated during an extended period by an oscillating massive scalar condensate. We show that during this period, sub-Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Karsten Jedamzik , Martin Lemoine , Jerome Martin

We probe the cosmological consequences of a recently proposed class of solutions to the cosmological constant problem. In these models, the universe undergoes a long period of inflation followed by a contraction and a bounce that sets the…

High Energy Physics - Phenomenology · Physics 2022-01-27 Lingyuan Ji , David E. Kaplan , Surjeet Rajendran , Erwin H. Tanin

We revisit the framework of axion-like inflation in view of the possibility that the coupling of the inflaton to a non-Abelian topological charge density could lead to the generation of a rapidly thermalizing heat bath. Both dispersive…

High Energy Physics - Phenomenology · Physics 2022-12-14 P. Klose , M. Laine , S. Procacci

It is now understood that inflation dynamics comes in two forms, isentropic or cold inflation and nonisentropic or warm inflation. In the former, inflation occurs without radiation production, whereas in the latter both radiation production…

High Energy Physics - Phenomenology · Physics 2007-05-23 Arjun Berera

The Cosmic Background Explorer (COBE) detection of microwave background anisotropies may contain a component due to gravitational waves generated by inflation. It is shown that the gravitational waves from inflation might be seen using…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Andrew R Liddle

We study the phenomenological constraints on a recently proposed model of open inflation in the context of induced gravity. The main interest of this model is the relatively small number of parameters, which may be constrained by many…

Astrophysics · Physics 2016-08-24 Juan Garcia-Bellido , Andrew R Liddle

Inflation is an early period of accelerated cosmic expansion, thought to be sourced by high energy physics. A key task today is to use the influx of increasingly precise observational data to constrain the plethora of inflationary models…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-05 Joseph Elliston

Scalar and tensorial cosmological perturbations generated in warm inflationary scenarios whose matter-radiation fluid is endowed with a viscous pressure are considered. Recent observational data from the WMAP experiment are employed to…

Astrophysics · Physics 2008-11-26 Sergio del Campo , Ramon Herrera , Diego Pavon

Inflation provides a unified paradigm for understanding the isotropy of the cosmic microwave background (CMB), the flatness problem, and the origin of large-scale structure. Although the physics responsible for inflation is not yet well…

Astrophysics · Physics 2015-06-24 Marc Kamionkowski

Taking field theory seriously, inflation model-building is difficult but not impossible. The observed value of the spectral index of the adiabatic density perturbation is starting to discriminate between models, and may well pick out a…

High Energy Physics - Phenomenology · Physics 2009-10-31 David H Lyth

I present a briefly summary of the current status of inflationary models versus topological defects scenarios, as the mechanisms which could have induced the initial density perturbations, which left an imprint on the cosmic microwave…

Astrophysics · Physics 2007-05-23 Mairi Sakellariadou

Most of the analysis of the Cosmic Microwave Background relies on the assumption of statistical isotropy. However, given some recent evidence pointing against isotropy, as for instance the observed alignment of different multipoles on large…

Astrophysics · Physics 2007-11-12 A. E. Gumrukcuoglu , Carlo R. Contaldi , Marco Peloso

We confront the warm inflation observational predictions directly with the latest CMB data. We focus on a linear temperature (T) dissipative coefficient combined with the simplest model of inflation, a quartic chaotic potential. Although…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-06 Mar Bastero-Gil , Sukannya Bhattacharya , Koushik Dutta , Mayukh Raj Gangopadhyay

We calculate the power spectrum of adiabatic density perturbations in an open inflationary model in which inflation occurs in two stages. First an epoch of old inflation creates a large, smooth universe, solving the horizon and homogeneity…

High Energy Physics - Phenomenology · Physics 2009-10-28 Martin Bucher , Neil Turok

Measurements of CMB anisotropy and, more recently, polarization have played a very important role allowing precise determination of various parameters of the `standard' cosmological model. The expectation of the paradigm of inflation and…

Astrophysics · Physics 2008-11-26 Tarun Souradeep

The observed baryon asymmetry, as well as potentially an asymmetry in the dark matter sector, can be produced through dissipative particle production during inflation. A distinctive feature of this mechanism is the generation of matter…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-29 Mar Bastero-Gil , Arjun Berera , Rudnei O. Ramos , Joao G. Rosa

The density perturbation during inflation seeds the large scale structure. We consider both new inflation-type and chaotic inflation-type potentials in the framework of Einstein-Brans-Dicke gravity. The density perturbation gives strong…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Yungui Gong

We investigate the primordial scalar perturbations in the thermal dissipative inflation where the radiation component (thermal bath) persists and the density fluctuations are thermally originated. The perturbation generated in this model is…

Astrophysics · Physics 2009-11-10 Wolung Lee , Li-Zhi Fang

In this article, we examine the effects of anisotropy on a model of canonical warm inflation with the power-law potential. The results of this model are compared to Planck satellite observational data. Using a conventional local scalar…

General Relativity and Quantum Cosmology · Physics 2022-05-05 Zahra Ghadiri , Ali Aghamohammadi , Abdollah Refaei