English
Related papers

Related papers: Non-Gaussianity from Axion Monodromy Inflation

200 papers

We calculate the trispectrum of curvature perturbations for a model of inflation endowed with Galilean symmetry at the level of the fluctuations around an FRW background. Such a model has been shown to posses desirable properties such as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Nicola Bartolo , Emanuela Dimastrogiovanni , Matteo Fasiello

Quasi-single field inflation predicts a peculiar momentum dependence in the squeezed limit of the primordial bispectrum which smoothly interpolates between the local and equilateral models. This dependence is directly related to the mass of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Emiliano Sefusatti , James R. Fergusson , Xingang Chen , E. P. S. Shellard

This article investigates the generation of non-Gaussianity during inflation. In the context of multi-field inflation, we detail a mechanism that can create significant primordial non-Gaussianities in the adiabatic mode while preserving the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Francis Bernardeau , Jean-Philippe Uzan

In this review, we discuss how non-Gaussianity of cosmological perturbations arises from inflation. After introducing the in-in formalism to calculate the $n$-point correlation function of quantum fields, we present the computation of the…

High Energy Physics - Theory · Physics 2014-11-20 Kazuya Koyama

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

We study an inflationary model developed by Kaloper and Sorbo, in which the inflaton is an axion with a sub-Planckian decay constant, whose potential is generated by mixing with a topological 4-form field strength. This gives a 4d…

High Energy Physics - Theory · Physics 2011-03-18 Nemanja Kaloper , Albion Lawrence , Lorenzo Sorbo

Models of cosmic inflation generically predict a weak but potentially detectable amount of primordial non-Gaussianity (PNG), which can be used to obtain insights into the degrees of freedom during inflation and their interactions. The…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-05 Anton Chudaykin , Mikhail M. Ivanov , Oliver H. E. Philcox

We study the inflation in a model with a Gauss-Bonnet term which is non-minimally coupled to a DBI field. We study the spectrum of the primordial perturbations in detail. The non-Gaussianity of this model is considered and the amplitude of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Kourosh Nozari , Narges Rashidi

Many models of inflation predict oscillatory features in the bispectrum of primordial fluctuations. Since it has been shown that primordial non-Gaussianity can lead to a scale-dependent halo bias, we investigate the effect of oscillations…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-20 Francis-Yan Cyr-Racine , Fabian Schmidt

An attractive candidate for the inflaton is an axion slowly rolling down a flat potential protected by a perturbative shift symmetry. Realisations of this idea within large field, natural and monomial inflation have been disfavoured by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Susha Parameswaran , Gianmassimo Tasinato , Ivonne Zavala

Primordial non-Gaussianity arising from inflationary models is a unique probe of non-trivial dynamics of the inflaton field and its interactions with other fields. Often when examining and constraining the scalar non-Gaussianity arising…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-17 Barnali Das , H. V. Ragavendra

We study the extension of the chromo-natural inflation model by incorporating nonminimal coupling between the axion field and gravity. Nonminimal coupling is introduced so that it enhances friction in the axion's equation of motion and thus…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-17 Tomoaki Murata , Tsutomu Kobayashi

We consider inflation driven by an axion-like particle coupled to an SU(2) gauge sector via a Chern-Simons term. Known as chromo-natural inflation, this scenario is in tension with CMB observations. In order to remedy this fact and preserve…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-21 Ema Dimastrogiovanni , Matteo Fasiello , Martino Michelotti , Lucas Pinol

We calculate the perturbed action, at second and third order, for a massive three-form field minimally coupled to gravity, and use it to explore the observational predictions of three-form inflation. One intriguing result is that the value…

Cosmology and Nongalactic Astrophysics · Physics 2014-02-11 David J. Mulryne , Johannes Noller , Nelson J. Nunes

To efficiently probe primordial non-Gaussianity using Cosmic Microwave Background (CMB) data, we require theoretical predictions that are factorizable, \textit{i.e.}\ those whose kinematic dependence can be separated. This property does not…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-25 Oliver H. E. Philcox , Kunhao Zhong , Salvatore Samuele Sirletti

The weak gravity conjecture imposes severe constraints on natural inflation. A trans-Planckian axion decay constant can only be realized if the potential exhibits an additional (subdominant) modulation with sub-Planckian periodicity. The…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Martin Wolfgang Winkler , Martina Gerbino , Micol Benetti

Models of inflation are instructive playgrounds for supersymmetry breaking in Supergravity and String Theory. In particular, combinations of branes and orientifolds that are not mutually BPS can lead to \emph{brane supersymmetry breaking},…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 A. Sagnotti

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent amplitude of the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Emiliano Sefusatti , Michele Liguori , Amit P. S. Yadav , Mark G. Jackson , Enrico Pajer

Recent developments in inflation model building, based on supersymmetry, have produced compelling models in which strings are produced at the end of inflation. In such models the cosmological perturbations are seeded both by the defects and…

Astrophysics · Physics 2009-10-31 Joao Magueijo , Carlo Contaldi , Mark Hindmarsh

In Chain Inflation the universe tunnels along a series of false vacua of ever-decreasing energy. The main goal of this paper is to embed Chain Inflation in high energy fundamental physics. We begin by illustrating a simple effective…

High Energy Physics - Theory · Physics 2022-04-20 Katherine Freese , Aliki Litsa , Martin Wolfgang Winkler