Scale-invariant quadratic gravity and inflation in the Palatini formalism

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F47813059%3A19630%2F21%3AA0000116" target="_blank" >RIV/47813059:19630/21:A0000116 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.aps.org/prd/abstract/10.1103/PhysRevD.104.023521" target="_blank" >https://journals.aps.org/prd/abstract/10.1103/PhysRevD.104.023521</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevD.104.023521" target="_blank" >10.1103/PhysRevD.104.023521</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Scale-invariant quadratic gravity and inflation in the Palatini formalism

Popis výsledku v původním jazyce

In the framework of classical scale invariance, we consider quadratic gravity in the Palatini formalism and investigate the inflationary predictions of the theory. Our model corresponds to a two-field scalar-tensor theory, which involves the Higgs field and an extra scalar field stemming from a gauge U(1)(X) extension of the Standard Model, which contains an extra gauge boson and three right-handed neutrinos. Both scalar fields couple nonminimally to gravity and induce the Planck scale dynamically, once they develop vacuum expectation values. By means of the Gildener-Weinberg approach, we describe the inflationary dynamics in terms of a single scalar degree of freedom along the flat direction of the tree-level potential. The one-loop effective potential in the Einstein frame exhibits plateaus on both sides of the minimum and thus the model can accommodate both small and large field inflation. The inflationary predictions of the model are found to comply with the latest bounds set by the Planck collaboration for a wide range of parameters and the effect of the quadratic in curvature terms is to reduce the value of the tensor-to-scalar ratio.

Název v anglickém jazyce

Scale-invariant quadratic gravity and inflation in the Palatini formalism

Popis výsledku anglicky

In the framework of classical scale invariance, we consider quadratic gravity in the Palatini formalism and investigate the inflationary predictions of the theory. Our model corresponds to a two-field scalar-tensor theory, which involves the Higgs field and an extra scalar field stemming from a gauge U(1)(X) extension of the Standard Model, which contains an extra gauge boson and three right-handed neutrinos. Both scalar fields couple nonminimally to gravity and induce the Planck scale dynamically, once they develop vacuum expectation values. By means of the Gildener-Weinberg approach, we describe the inflationary dynamics in terms of a single scalar degree of freedom along the flat direction of the tree-level potential. The one-loop effective potential in the Einstein frame exhibits plateaus on both sides of the minimum and thus the model can accommodate both small and large field inflation. The inflationary predictions of the model are found to comply with the latest bounds set by the Planck collaboration for a wide range of parameters and the effect of the quadratic in curvature terms is to reduce the value of the tensor-to-scalar ratio.

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/GA19-03950S" target="_blank" >GA19-03950S: Testování silné gravitace prostřednictvím černých děr</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Physical Review D

ISSN

2470-0010

e-ISSN

2470-0029

Svazek periodika

104

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

20

Strana od-do

„023521-1“-„023521-20“

Kód UT WoS článku

000675556000001

EID výsledku v databázi Scopus

2-s2.0-85112749335