J 2023

Implications of Palatini gravity for inflation and beyond

GIALAMAS, Ioannis D., Alexandros KARAM, Thomas PAPPAS and Eemeli TOMBERG

Basic information

Original name

Implications of Palatini gravity for inflation and beyond

Authors

GIALAMAS, Ioannis D., Alexandros KARAM, Thomas PAPPAS (300 Greece, belonging to the institution) and Eemeli TOMBERG

Edition

INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS, 2023, 0219-8878

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10308 Astronomy

Country of publisher

Singapore

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

RIV identification code

RIV/47813059:19630/23:A0000294

Organization unit

Institute of physics in Opava

UT WoS

001036959400003

Keywords in English

Cosmic inflation;Palatini gravity;review

Tags

Tags

International impact, Reviewed
Změněno: 13/2/2024 14:59, Mgr. Pavlína Jalůvková

Abstract

V originále

In this paper, we present an introduction to cosmic inflation in the framework of Palatini gravity, which provides an intriguing alternative to the conventional metric formulation of gravity. In the latter, only the metric specifies the spacetime geometry, whereas in the former, the metric and the spacetime connection are independent variables-an option that can result in a gravity theory distinct from the metric one. In scenarios where the field(s) responsible for cosmic inflation are non-minimally coupled to gravity or the gravitational sector is extended, assumptions about the underlying gravitational degrees of freedom can have substantial implications for the observational effects of inflation. We examine this explicitly by discussing various compelling scenarios, such as Higgs inflation with a non-minimal coupling to gravity, Higgs inflation with a non-minimal derivative coupling, R-2 inflation, and beyond. We also comment on reheating in these models. Finally, as an application of the general results of Palatini R-2 inflation, we review a model of successful quintessential inflation, where a single scalar field acts initially as the inflaton and then becomes dynamical dark energy, in agreement will all experimental constraints.