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Related papers: Anisotropic warm inflation

200 papers

We identify a new mechanism in supergravity theories which leads to successful inflation without any need for fine tuning. The simplest model yields a spectrum of density fluctuations tilted away from scale-invariance and negligible…

High Energy Physics - Phenomenology · Physics 2014-11-17 Jennifer A. Adams , Graham G. Ross , Subir Sarkar

We present a comprehensive study of warm hybrid inflation within the framework of $\alpha$-attractor models, where an axionic inflaton is coupled to a waterfall field in the presence of thermal dissipation. The model is analyzed for both…

High Energy Physics - Phenomenology · Physics 2026-01-16 Waqas Ahmed , Waqar Ahmad , Ahsan Illahi , M. Junaid

In this paper, we study a non-canonical extension of a supergravity-motivated model acting as a vivid counterexample to the cosmic no-hair conjecture due to its unusual coupling between scalar and electromagnetic fields. In particular, a…

General Relativity and Quantum Cosmology · Physics 2021-09-23 Duy H. Nguyen , Tuyen M. Pham , Tuan Q. Do

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

We examine the behavior of an anisotropic brane-world in the presence of inflationary scalar fields. We show that, contrary to naive expectations, a large anisotropy does not adversely affect inflation. On the contrary, a large initial…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Roy Maartens , Varun Sahni , Tarun Deep Saini

We study the emergence of anisotropic (Bianchi IX) inflationary universes with no-boundary conditions in the path integral approach to quantum gravity. In contrast to previous work, we find no evidence for any limit to how large the…

High Energy Physics - Theory · Physics 2017-04-19 Sebastian F. Bramberger , Shane Farnsworth , Jean-Luc Lehners

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

We study anisotropic inflation in the Brans-Dicke gravity in the presence of an abelian gauge field where the gauge field is non-minimally coupled to the inflaton. We show that the degree of anisotropy, under slow-roll approximations, is…

General Relativity and Quantum Cosmology · Physics 2017-11-03 M. Tirandari , Kh. Saaidi

We study dynamical condensation process in a holographic superconductor model with anisotropy. The time-dependent numerical solution is constructed for the Einstein-Maxwell-dilaton theory with complex scalar in asymptotic AdS spacetime. The…

High Energy Physics - Theory · Physics 2014-09-17 Xiaojian Bai , Bum-Hoon Lee , Miok Park , Khimphun Sunly

We examined the chromo-natural inflation in the context of warm inflation with variable dissipation coefficient. The dynamical equations of this model are obtained. We studied the cosmological perturbation theory in this model. The sources…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-30 Sabina Yeasmin , Atri Deshamukhya

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

In presence of Gauss-Bonnet corrections, we study anisotropic inflation aided by a massless $SU(2)$ gauge field where both the gauge field and the Gauss-Bonnet term are non-minimally coupled to the inflaton. In this scenario, under…

High Energy Physics - Theory · Physics 2017-01-18 Sayantani Lahiri

This article provides an introductory review of inflation and cosmological perturbation theory. I begin by motivating the need for an epoch of inflation during the early stages of the radiation dominated era, and describe how inflation is…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-08 L. Sriramkumar

Bouncing cosmologies are often proposed as alternatives to standard inflation for the explanation of the homogeneity and flatness of the universe. In such scenarios, the present cosmological expansion is preceded by a contraction phase.…

High Energy Physics - Theory · Physics 2010-04-30 V. Bozza , M. Bruni

The axion is a well-motivated candidate for the inflaton, as the radiative corrections that spoil many single-field models are avoided by virtue of its shift symmetry. However, axions generically couple to gauge sectors. As the axion…

High Energy Physics - Phenomenology · Physics 2021-11-09 William DeRocco , Peter W. Graham , Saarik Kalia

Warm natural inflation is studied for the case of the original cosine potential. The radiation bath during inflation induces a dissipation (friction) rate in the equation of motion for the inflaton field, which can potentially reduce the…

General Relativity and Quantum Cosmology · Physics 2023-03-08 Gabriele Montefalcone , Vikas Aragam , Luca Visinelli , Katherine Freese

Noncommutative inflation is based upon the consideration of some effects of the space-time uncertainty principle motivated by ideas from string/M theory. The CMB anisotropies may carry a signature of this very early Universe correction from…

Astrophysics · Physics 2009-11-11 Xin Zhang , Feng-Quan Wu

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

We consider a model of inflation consisting a single fluid with a time-dependent equation of state. In this phenomenological picture, two periods of inflation are separated by an intermediate non-inflationary stage which can be either a…

High Energy Physics - Theory · Physics 2015-06-05 Mohammad Hossein Namjoo , Hassan Firouzjahi , Misao Sasaki

We consider an alternative warm inflationary scenario in which $n$ scalar fields coupled to a dissipative matter fluid cooperate to produce power--law inflation. The scalar fields are driven by an exponential potential and the bulk…

Astrophysics · Physics 2009-11-07 Luis P. Chimento , Alejandro S. Jakubi , Diego Pavón , Norberto A. Zuccala