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Related papers: Mixed non-Gaussianity in multiple-DBI inflation

200 papers

We study the generation of non-Gaussianity in models of hybrid inflation with two inflaton fields, (2-brid inflation). We analyse the region in the parameter and the initial condition space where a large non-Gaussianity may be generated…

Astrophysics · Physics 2010-04-30 Christian T. Byrnes , Ki-Young Choi , Lisa M. H. Hall

We investigate non-Gaussianity in general multiple-field inflation using the formalism we developed in earlier papers. We use a perturbative expansion of the non-linear equations to calculate the three-point correlator of the curvature…

Astrophysics · Physics 2009-11-13 G. I. Rigopoulos , E. P. S. Shellard , B. J. W. van Tent

We study cosmological perturbations in general inflation models with multiple scalar fields and arbitrary kinetic terms, with special emphasis on the multi-field extension of Dirac-Born-Infeld (DBI) inflation. We compute the second-order…

High Energy Physics - Theory · Physics 2008-12-18 David Langlois , Sebastien Renaux-Petel , Daniele A. Steer , Takahiro Tanaka

We investigate an estimator to measure the primordial trispectrum in equilateral type non-Gaussian models such as k-inflation, single field DBI inflation and multi-field DBI inflation models from Cosmic Microwave Background (CMB)…

High Energy Physics - Theory · Physics 2014-11-21 Shuntaro Mizuno , Kazuya Koyama

We explore the superhorizon generation of large fnl of the local form in two field inflation. We calculate the two- and three-point observables in a general class of potentials which allow for an analytic treatment using the delta N…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-17 Joel Meyers , Navin Sivanandam

Extending the analysis of [1011.4934] beyond the bispectrum, we explore the superhorizon generation of local non-gaussianities and their subsequent approach to adiabaticity. Working with a class of two field models of inflation with…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-06 Joel Meyers , Navin Sivanandam

We study the evolution of non-Gaussianity in multiple-field inflationary models, focusing on three fundamental questions: (a) How is the sign and peak magnitude of the non-linearity parameter fNL related to generic features in the…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-07 Joseph Elliston , David Mulryne , David Seery , Reza Tavakol

A model of multi-component hybrid inflation, dubbed multi-brid inflation, in which various observable quantities including the non-Gaussianity parameter f_{NL} can be analytically calculated was proposed recently. In particular, for a…

Astrophysics · Physics 2009-10-09 Atsushi Naruko , Misao Sasaki

We discuss the effect of superimposing multiple sources of resonant non-Gaussianity, which arise for instance in models of axion inflation. The resulting sum of oscillating shape contributions can be used to "Fourier synthesize" different…

High Energy Physics - Theory · Physics 2013-06-18 Rhiannon Gwyn , Markus Rummel , Alexander Westphal

For very general scalar-field theories in which the equations of motion are at second-order, we evaluate the three-point correlation function of primordial scalar perturbations generated during inflation. We show that the shape of…

General Relativity and Quantum Cosmology · Physics 2011-10-11 Antonio De Felice , Shinji Tsujikawa

Focusing on the local type primordial non-Gaussianities, we study the bispectrum and trispectrum during a non-minimal slow-roll inflation. We use the so-called $\delta N$ formalism to investigate the super-horizon evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-28 Kosar Asadi , Kourosh Nozari

We study the bispectrum of the curvature perturbation on uniform energy density hypersurfaces in models of inflation with two scalar fields evolving simultaneously. In the case of a separable potential, it is possible to compute the…

Astrophysics · Physics 2009-11-11 Filippo Vernizzi , David Wands

We have studied primordial non-Gaussian features from a model of potential driven single field DBI Galileon inflation. We have computed the bispectrum from the three point correlation function considering all possible cross correlation…

High Energy Physics - Theory · Physics 2015-06-08 Sayantan Choudhury , Supratik Pal

Canonical models of single-field, slow-roll inflation do not lead to appreciable non-Gaussianity, unless derivative interactions of the inflaton become uncontrollably large. We propose a novel slow-roll scenario where scalar perturbations…

High Energy Physics - Theory · Physics 2016-05-25 David Pirtskhalava , Luca Santoni , Enrico Trincherini , Filippo Vernizzi

We derive semi-analytic formulae for the local bispectrum and trispectrum in general two-field inflation and provide a simple geometric recipe for building observationally allowed models with observable non-Gaussianity. We use the \delta N…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Courtney M. Peterson , Max Tegmark

The general expression for the second order large scale curvature perturbation in the form of a functional over a background solution is derived. The explicit expressions was obtained for two special forms of the inflationary potential. In…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-26 N. A. Koshelev

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 present a method for implementing the $\delta N$ formalism to study the primordial non-Gaussianity produced in multiple three-form field inflation. Using a dual description relating three-form fields to noncanonical scalar…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 K. Sravan Kumar , David J. Mulryne , Nelson J. Nunes , João Marto , Paulo Vargas Moniz

We study the slow-roll inflation models, where the inflaton slow-rolls along a trajectory whose orthogonal directions are lifted by potentials with masses of order the Hubble parameter. In these models large non-Gaussianities can be…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Xingang Chen , Yi Wang

Local-type primordial non-Gaussianity couples statistics of the curvature perturbation \zeta on vastly different physical scales. Because of this coupling, statistics (i.e. the polyspectra) of \zeta in our Hubble volume may not be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Marilena LoVerde , Elliot Nelson , Sarah Shandera