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Related papers: Equilateral non-Gaussianity from heavy fields

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We propose an inflationary scenario inspired by a recent formulation, in terms of coherent states, of non-commutative quantum field theory. We consider the semiclassical Einstein equations, and we exploit the ultraviolet finiteness of the…

General Relativity and Quantum Cosmology · Physics 2011-04-28 Massimiliano Rinaldi

The scalar mode density perturbations in a the warm inflationary scenario are analysed with a view to predicting the amount of non-gaussianity produced by this scenario. The analysis assumes that the inflaton evolution is strongly damped by…

Astrophysics · Physics 2010-10-27 Ian G Moss , Chun Xiong

We study a model of multiple-field DBI inflation leading to mixed form of primordial non-Gaussianity, including equilateral and local bispectrum shapes. We present a general formalism based on the Hamilton-Jacobi approach, allowing us to go…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-23 Jon Emery , Gianmassimo Tasinato , David Wands

For simple inflationary models, we provide a consistent and complete scheme by which the macro-physical details of early universe inflation may be determined explicitly from the underlying micro-physical theory. We examine inflationary…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Cormier

Multiple fields can become dynamical during the inflationary epoch. We consider an example where a light field acquires isocurvature fluctuations during inflation and contributes to the dark matter abundance at late times. Interactions…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-08 Michael Geller , Soubhik Kumar , Lian-Tao Wang

Primordial non-Gaussianity signatures of extremely heavy particles are re-examined within a simple alternative to the standard inflationary paradigm, in which the primordial fluctuations and the inflationary spacetime expansion are sourced…

High Energy Physics - Phenomenology · Physics 2020-06-05 Soubhik Kumar , Raman Sundrum

Detection of primordial non-Gaussianity will give us an unprecedented detail of the physics of inflation. As observational probes are now exploring new expanses of the inflationary landscape, it is crucial to distinguish and disentangle…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-16 Sirichai Chongchitnan

We study the effects of non-trivial initial quantum states for inflationary fluctuations within the context of the effective field theory for inflation constructed by Cheung et al. which allows us to discriminate between different initial…

High Energy Physics - Theory · Physics 2013-11-20 Nishant Agarwal , R. Holman , Andrew J. Tolley , Jennifer Lin

We investigated the possibility that nonlinear gravitational effects influence the preheating era after inflation, using numerical solutions of the inhomogeneous Einstein field equations. We compared our results to perturbative calculations…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Matthew Parry , Richard Easther

DHOST inflation models where deviations from a pure de Sitter background are induced by an axion-like potential can lead to large non-Gaussianities. We investigate the nature of non-Gaussianities in these models and compare to the results…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Philippe Brax , Andrei Lazanu

Gauge-flation, non-Abelian gauge field inflation, which was introduced in arXiv:1102.1513 and analyzed more thoroughly in arXiv:1102.1932, is a model of inflation driven by non-Abelian gauge fields minimally coupled to Einstein gravity. In…

High Energy Physics - Theory · Physics 2015-06-04 M. M. Sheikh-Jabbari

We analyze the shape and amplitude of oscillatory features in the primordial power spectrum and non-Gaussianity induced by periodic production of heavy degrees of freedom coupled to the inflaton $\phi$. We find that non-adiabatic production…

High Energy Physics - Theory · Physics 2017-11-15 Raphael Flauger , Mehrdad Mirbabayi , Leonardo Senatore , Eva Silverstein

We consider primordial fluctuations in thermal inflation scenario. Since the thermal inflation drives about 10 $e$-folds after the standard inflation, the time of horizon-exit during inflation corresponding to the present observational…

High Energy Physics - Theory · Physics 2010-02-18 Masahiro Kawasaki , Tomo Takahashi , Shuichiro Yokoyama

We study the second-order gauge-invariant adiabatic and isocurvature perturbations in terms of the scalar fields present during inflation, along with the related fully non-linear space gradient of these quantities. We discuss the relation…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-01 Eleftheria Tzavara , Bartjan van Tent

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

The gravitationally enhanced friction can reduce the speed of the inflaton to realize an ultra-slow-roll inflation, which will amplify the curvature perturbations. The amplified perturbations can generate a sizable amount of primordial…

General Relativity and Quantum Cosmology · Physics 2022-10-27 Li-Yang Chen , Hongwei Yu , Puxun Wu

Single scalar field inflation with a generic, non-quadratic in derivatives, field Lagrangian is considered. It is shown that non-Gaussianity of curvature perturbations is characterized by two dimensionless amplitudes. One of these…

Astrophysics · Physics 2009-11-10 Andrei Gruzinov

We consider the description of the clustering of halos for physically-motivated types of non-Gaussian initial conditions. In particular we include non-Gaussianity of the type arising from single field slow-roll, multi fields, curvaton…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Licia Verde , Sabino Matarrese

We evaluate the quantum backreaction due to a gauge field coupled to a pseudo-scalar field driving a slow-roll inflationary stage, the so-called axion inflation. The backreaction is evaluated for the first time using a gauge invariant…

General Relativity and Quantum Cosmology · Physics 2024-10-23 Davide Campanella Galanti , Pietro Conzinu , Giovanni Marozzi , Simony Santos da Costa

In this article, we study in detail the linear dynamics and cubic interactions for any number $N_\mathrm{field}$ of scalar fields during inflation, directly in terms of the observable curvature perturbation $\zeta$ and $N_\mathrm{field}-1$…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-11 Lucas Pinol
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