English
Related papers

Related papers: A case for kinetically dominated initial condition…

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

In this paper we investigate the induced inflation with two flat regions: one Starobinsky-like plateau in big field regime and one shorter plateau around the saddle point of the Einstein frame potential. This multi-phase inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 Michal Artymowski , Zygmunt Lalak , Marek Lewicki

In this work we introduce a new plateau-like inflationary model including a quadratic scalar potential coupled non-minimally to gravity. This potential has a dominant constant energy density at early times which can realize successful…

High Energy Physics - Theory · Physics 2015-11-30 Mehdi Eshaghi , Moslem Zarei , Nematollah Riazi , Ahmad Kiasatpour

We consider cosmological scenarios in which density perturbations are generated by the quantum fluctuations of the inflaton field at early times; the late time dynamics involves a modulus which first dominates the energy density of the…

High Energy Physics - Phenomenology · Physics 2015-03-09 Koushik Dutta , Anshuman Maharana

In scenarios of physical interest in Loop Quantum Cosmology, with a preinflationary epoch where the kinetic energy of the inflaton dominates, the analytic study of the dynamics of the primordial fluctuations has been carried out by…

General Relativity and Quantum Cosmology · Physics 2023-11-03 Beatriz Elizaga Navascués , Guillermo A. Mena Marugán , Jesús Yébana Carrilero

Motivated by the idea that inflation occurs at the GUT symmetry breaking scale, in this paper we construct a new class of large field inflaton potentials where the inflaton starts with a power law potential; after initial period of relative…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-24 Dhiraj Kumar Hazra , Arman Shafieloo , George F. Smoot , Alexei A. Starobinsky

We study a scalar field with non-minimal kinetic coupling to itself and to the curvature. The slow rolling conditions allowing an inflationary background have been found. The quadratic and Higgs type potentials have been considered, and the…

High Energy Physics - Theory · Physics 2011-05-12 L. N. Granda

We propose a chaotic inflation model in supergravity based on polynomial interactions of the inflaton. Specifically we study the chaotic inflation model with quadratic, cubic and quartic couplings in the scalar potential and show that the…

High Energy Physics - Phenomenology · Physics 2015-06-15 Kazunori Nakayama , Fuminobu Takahashi , Tsutomu T. Yanagida

We study primordial perturbations from hyperinflation, proposed recently and based on a hyperbolic field-space. In the previous work, it was shown that the field-space angular momentum supported by the negative curvature modifies the…

High Energy Physics - Theory · Physics 2017-12-08 Shuntaro Mizuno , Shinji Mukohyama

Space-based missions studying the cosmic microwave background (CMB) have progressively refined the parameter space in conventional models of inflation shortly ($\sim 10^{-37}$ seconds) after the big bang. While most inflationary scenarios…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-18 Jingwei Liu , Fulvio Melia

We place observational constraints on slow-variation single-field inflationary models by carrying out the cosmological Monte Carlo simulation with the recent data of Planck combined with the WMAP large-angle polarization, baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-12 Shinji Tsujikawa , Junko Ohashi , Sachiko Kuroyanagi , Antonio De Felice

We consider the behaviour of a quintessence field during an inflationary epoch, in order to learn how inflation influences the likely initial conditions for quintessence. We use the stochastic inflation formalism to study quantum…

Astrophysics · Physics 2009-11-07 Michael Malquarti , Andrew R Liddle

The viability of a given model for inflation is determined not only by the form of the inflaton potential, but also by the initial inflaton field configuration. In many models, field configurations which are otherwise well-motivated…

High Energy Physics - Theory · Physics 2019-10-16 Keith R. Dienes , Jeff Kost , Brooks Thomas

Many different models of inflation give rise to the same effective field theory of the inflaton. While effective field theories in flat space provide little information about UV physics, we propose that in inflationary backgrounds a large…

High Energy Physics - Theory · Physics 2012-01-04 Ross O'Connell , R. Holman

Using numerical solutions of the full Einstein field equations coupled to a scalar inflaton field in 3+1 dimensions, we study the conditions under which a universe that is initially expanding, highly inhomogeneous and dominated by gradient…

High Energy Physics - Theory · Physics 2016-09-07 William E. East , Matthew Kleban , Andrei Linde , Leonardo Senatore

I discuss folded inflation, an inflationary model embedded in a multi-dimensional scalar potential, such as the stringy landscape. During folded inflation, the field point evolves along a path that turns several corners in the potential.…

High Energy Physics - Theory · Physics 2007-05-23 Richard Easther

We discuss the issue of setting appropriate initial conditions for inflation. Specifically, we consider natural inflation model and discuss the fine tuning required for setting almost homogeneous initial conditions over a region of order…

High Energy Physics - Theory · Physics 2021-05-17 Partha Bagchi , Arpan Das , Shreyansh S. Dave , Srikumar Sengupta , Ajit M. Srivastava

We show how a radiation dominated universe subject to space-time quantization may give rise to inflation as the radiation temperature exceeds the Planck temperature. We consider dispersion relations with a maximal momentum (i.e. a mimimum…

High Energy Physics - Theory · Physics 2009-11-07 Stephon Alexander , Robert Brandenberger , Joao Magueijo

We develop a consistent analytic approach to determine the conditions under which slow roll inflation can arise when the inflaton is the same scalar field that is responsible for the bounce in Loop Quantum Cosmology (LQC). We find that the…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Anshuman Bhardwaj , Edmund J. Copeland , Jorma Louko

We are in the era of precision cosmology which offers us a unique opportunity to investigate beyond standard model physics. Toward this endeavor, inflaton is assumed to be a perfect new physics candidate. In this submission, we explore the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-20 Ayan Chakraborty , Md Riajul Haque , Debaprasad Maity , Rajesh Mondal