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Related papers: Large trispectrum in two-field slow-roll inflation

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Motivated by the recent `Higgs-inflation' scenario based on a single inflaton field, we consider more generic two-field inflation with non-minimal coupling term. The generic analytic expressions are derived for cosmological observables with…

High Energy Physics - Phenomenology · Physics 2015-03-13 Jinsu Kim , Yoonbai Kim , Seong Chan Park

Multiple inflation is a model based on N=1 supergravity wherein there are sudden changes in the mass of the inflaton because it couples to 'flat direction' scalar fields which undergo symmetry breaking phase transitions as the universe…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Shaun Hotchkiss , Subir Sarkar

In this work we study slow-roll inflation for a vector-tensor model with massive vector fields non-minimally coupled to gravity. The model under consideration has arbitrary parameters for each geometrical coupling. Taking into account a…

General Relativity and Quantum Cosmology · Physics 2016-12-21 A. Oliveros

We generalize the Effective Field Theory of Inflation to include additional light scalar degrees of freedom that are in their vacuum at the time the modes of interest are crossing the horizon. In order to make the scalars light in a natural…

High Energy Physics - Theory · Physics 2015-05-19 Leonardo Senatore , Matias Zaldarriaga

We present a new and accurate Fortran code, the BI-spectra and Non-Gaussianity Operator (BINGO), for the efficient numerical computation of the scalar bi-spectrum and the non-Gaussianity parameter f_{NL} in single field inflationary models…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Dhiraj Kumar Hazra , L. Sriramkumar , Jerome Martin

We study the dual 3d Euclidean RG flow of single-field slow-roll Inflation using the postulates of the dS/CFT correspondence. For that purpose we solve for the inflationary fluctuation at all times using a matching procedure between two…

High Energy Physics - Theory · Physics 2015-06-17 Uri Kol

We compare the standard single scalar field inflationary predictions with those of an inflationary phase driven by a tachyon field. A slow-roll formalism is defined for tachyon inflation and we derive the spectra of scalar and tensor…

Astrophysics · Physics 2016-11-09 Filippo Vernizzi , Daniele Steer

We study an inflationary scenario where thermal inflation is followed by fast-roll inflation. This is a rather generic possibility based on the effective potentials of spontaneous symmetry breaking in the context of particle physics models.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jinn-Ouk Gong

We calculate the spectral index and tensor-to-scalar ratio for patch inflation arisen from the Gauss-Bonnet braneworld scenario. The patch cosmological models consist of Gauss-Bonnet (GB), Randall-Sundrum (RS), and 4D general relativistic…

Astrophysics · Physics 2010-04-05 Hungsoo Kim , Kyong Hee Kim , Hyung Won Lee , Yun Soo Myung

We study an inflationary model driven by a single minimally coupled standard kinetic term scalar field with a step in its mass modeled by an Heaviside step function. We present an analytical approximation for the mode function of the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-04 Frederico Arroja , Antonio Enea Romano , Misao Sasaki

We study small field models of inflation, which, against previous expectations, yield significant Gravitational Wave (GW) signal while reproducing other measured observable quantities in the Cosmic Microwave Background (CMB). We numerically…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-01 Ira Wolfson

We study tachyon inflation within the large-$N$ formalism, which takes a prescription for the small Hubble flow slow--roll parameter $\epsilon_1$ as a function of the large number of $e$-folds $N$. This leads to a classification of models…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-22 Nandinii Barbosa-Cendejas , Josue De-Santiago , Gabriel German , Juan Carlos Hidalgo , Refugio Rigel Mora-Luna

We argue that in models of inflation with two scalar fields and non-canonical kinetic terms there is a possibility of obtaining a red tilt of the power spectrum of curvature perturbations from noncanonicality-induced interactions between…

High Energy Physics - Theory · Physics 2015-03-17 Sera Cremonini , Zygmunt Lalak , Krzysztof Turzynski

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

In this paper, we compute the inflationary trispectrum of primordial gauge fields generated through the scalar and tensor exchanges in models with spectator $U(1)$ gauge fields which are kinetically coupled to the inflaton. Focusing on the…

High Energy Physics - Theory · Physics 2025-09-16 P. Jishnu Sai , S. R. Haridev , Rajeev Kumar Jain

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

We calculate the trispectrum of the primordial curvature perturbation generated by an epoch of slow-roll inflation in the early universe, and demonstrate that the non-gaussian signature imprinted at horizon crossing is unobservably small,…

Astrophysics · Physics 2010-10-27 David Seery , James E. Lidsey , Martin S. Sloth

A scalar field rolling down a potential with a large initial velocity results in inflation of a finite duration. Such a scenario suppresses the scalar power on large scales improving the fit to the cosmological data. We find that the…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 H. V. Ragavendra , Debika Chowdhury , L. Sriramkumar

Motivated by trans-Planckian issues in inflation, we determine the Hilbert space and amplitudes of quantum perturbations in the general low-energy effective theory of (multi-)field inflation without relying on the sub-horizon limit. The…

High Energy Physics - Theory · Physics 2026-05-29 Andrea Ambrosi de Magistris , Alberto Salvio

The standard calculation of the spectrum of density perturbations produced during inflation assumes (i) |n-1| << 1 and (ii) |dn/dlnk| << |n-1|. Slow-roll predicts and observations require (i), but neither slow-roll nor observations require…

Astrophysics · Physics 2009-11-07 Ewan D. Stewart
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