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Related papers: Shapes of non-Gaussianity in warm inflation

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An axion-like inflaton coupled to non-Abelian gauge bosons provides a compelling microphysical framework for warm inflation. Starting even from cold initial conditions, in these systems, sphaleron heating may generate thermal friction…

High Energy Physics - Phenomenology · Physics 2026-03-16 Mar Bastero-Gil , Pedro García Osorio , António Torres Manso

The general kind noncanonical warm inflation is introduced and its total non-Gaussianity of perturbation on uniform energy density hypersurfaces is studied. The total non-Gaussianity contains two complementary parts: the three- and the…

General Relativity and Quantum Cosmology · Physics 2019-12-19 Xiao-Min Zhang , Kai Li , Hong-Yang Ma , Qian Liu , Jian-Yang Zhu

We study non-Gaussianities in the primordial perturbations in single field inflation where there is radiation era prior to inflation. Inflation takes place when the energy density of radiation drops below the value of the potential of a…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-30 Suratna Das , Subhendra Mohanty

This paper presents and investigates non-Gaussian perturbations for the warm k-inflation model that is driven by pure kinetic energy. The two complementary components of the overall non-Gaussianity are the three-point and four-point…

General Relativity and Quantum Cosmology · Physics 2023-06-28 Chao-Qun Shen , Xiao-Min Zhang , Zhi-Peng Peng , He Liu , Xi-Bin Li , Peng-Cheng Chu

At finite temperature, the coupling of an axion to non-Abelian gauge fields causes dissipation due to sphaleron heating. This mechanism has been considered as ideal for realizing warm inflation since it can lead to large thermal friction…

High Energy Physics - Phenomenology · Physics 2025-10-21 Sebastian Zell

Non-Gaussianity generated in inflation can be contributed by two parts. The first part, denoted by $f_{NL}^{\delta N}$, is the contribution from four-point correlation of inflaton field which can be calculated using $\delta N$ formalism,…

General Relativity and Quantum Cosmology · Physics 2017-09-06 Xiao-Min Zhang , Hong-Yang Ma , Peng-Cheng Chu , Jian-Yang Zhu

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 propose the first model of warm inflation in which the particle production emerges directly from coupling the inflaton to Standard Model particles. Warm inflation, an early epoch of sustained accelerated expansion at finite temperature,…

High Energy Physics - Phenomenology · Physics 2024-11-15 Kim V. Berghaus , Matthew Forslund , Mark Vincent Guevarra

In this note, we will introduce an action for warm inflation model with direct coupling between the pseudoscalar field and mass-less $SU(2)$ gauge fields. The potential of inflaton is protected against the thermal corrections in a thermal…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Vahid. Kamali

We study the scalar-tensor-tensor non-Gaussian signal in an inflationary model comprising also an axion coupled with SU(2) gauge fields. In this set-up, metric fluctuations are sourced by the gauge fields already at the linear level…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-28 Emanuela Dimastrogiovanni , Matteo Fasiello , Robert J. Hardwick , Hooshyar Assadullahi , Kazuya Koyama , David Wands

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

This paper presents and investigates non-Gaussian perturbations for the warm k-inflation model that is driven by pure kinetic energy. The two complementary components of the overall non-Gaussianity are the three-point and four-point…

General Relativity and Quantum Cosmology · Physics 2025-11-21 Xiao-Min Zhang , Run-Qing Zhao , Yun-Cai Feng , Peng-Cheng Chu , Zhi-Peng Peng , Xi-Bin Li

Slow-roll inflation is a successful paradigm. However we find that even a small coupling of the inflaton to other light fields can dramatically alter the dynamics and predictions of inflation. As an example, the inflaton can generically…

High Energy Physics - Phenomenology · Physics 2023-09-19 Kim V. Berghaus , Peter W. Graham , David E. Kaplan

If cosmic inflation suffered tiny time-dependent deviations from the slow-roll regime, these would induce the existence of small scale-dependent features imprinted in the primordial spectra, with their shapes and sizes revealing information…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Sander Mooij , Gonzalo A. Palma , Grigoris Panotopoulos , Alex Soto

Inflaton couplings during warm inflation result in the production of a thermal bath. Thermal friction and fluctuations can dominate the standard de Sitter analogues, resulting in a modified slow-roll scenario with a new source of density…

High Energy Physics - Phenomenology · Physics 2026-05-22 Edward Broadberry , Anson Hook , Sagnik Mondal

The bispectrum of scalar mode density perturbations is analysed for the strong regime of warm inflationary models. This analysis generalises previous results by allowing damping terms in the inflaton equation of motion that are dependent on…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Ian G Moss , Timothy Yeomans

A numerical study of a pseudoscalar inflation having an axion-photon-like coupling is performed by solving numerically the coupled differential equations of motion for inflaton and photon mode functions from the onset of inflation to the…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 Shu-Lin Cheng , Wolung Lee , Kin-Wang Ng

We consider a quasi-single field inflation model in which the inflaton interacts with a massive scalar field called the isocurvaton. Due to the breaking of time translational invariance by the inflaton background, these interactions induce…

High Energy Physics - Phenomenology · Physics 2018-06-27 Haipeng An , Michael McAneny , Alexander K. Ridgway , Mark B. Wise

We calculate the general solutions for a warm inflationary scenario with weak dissipation, reviewing the dissipative dynamics of the two-fluid system, and calculate the bispectrum of the gravitational field fluctuations generated in the…

Astrophysics · Physics 2008-11-26 Sujata Gupta

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
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