Nonlinear perturbations from axion-gauge fields dynamics during inflation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F19%3A00522515" target="_blank" >RIV/68378271:_____/19:00522515 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.1088/1475-7516/2019/07/004" target="_blank" >https://doi.org/10.1088/1475-7516/2019/07/004</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1475-7516/2019/07/004" target="_blank" >10.1088/1475-7516/2019/07/004</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Nonlinear perturbations from axion-gauge fields dynamics during inflation

Popis výsledku v původním jazyce

We study a variant of the Chromo-Natural Inflation (CNI) mechanism in which the inflaton interacts only gravitationally with the CNI fields. Integrating out all the non-dynamical scalar fields of the model results in a coupling between the perturbations of the inflaton and of the CNI pseudo-scalar which is significantly greater than the one obtained in the absence of the gauge CNI dynamics. We compute how this greater coupling impacts the power spectrum of the inflaton perturbations that are sourced nonlinearly by the unstable (tensor) gauge CNI modes, and we require that the amplitude of these modes is well below that of the linear perturbations. Combining this result with various constraints, including backreaction effects, the requirement of having observable and dominant sourced gravitational waves (GW), and the current upper bound on the tensor-to-scalar ratio, significantly constrains the range of parameter space where this model can produce an interesting GW signal.

Název v anglickém jazyce

Nonlinear perturbations from axion-gauge fields dynamics during inflation

Popis výsledku anglicky

We study a variant of the Chromo-Natural Inflation (CNI) mechanism in which the inflaton interacts only gravitationally with the CNI fields. Integrating out all the non-dynamical scalar fields of the model results in a coupling between the perturbations of the inflaton and of the CNI pseudo-scalar which is significantly greater than the one obtained in the absence of the gauge CNI dynamics. We compute how this greater coupling impacts the power spectrum of the inflaton perturbations that are sourced nonlinearly by the unstable (tensor) gauge CNI modes, and we require that the amplitude of these modes is well below that of the linear perturbations. Combining this result with various constraints, including backreaction effects, the requirement of having observable and dominant sourced gravitational waves (GW), and the current upper bound on the tensor-to-scalar ratio, significantly constrains the range of parameter space where this model can produce an interesting GW signal.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/EF15_003%2F0000437" target="_blank" >EF15_003/0000437: Kosmologie, gravitace a temný sektor vesmíru</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Cosmology and Astroparticle Physics

ISSN

1475-7516

e-ISSN

—

Svazek periodika

2019

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

39

Strana od-do

1-39

Kód UT WoS článku

000476861200004

EID výsledku v databázi Scopus

2-s2.0-85071877510