Nonlocal gravity cosmology: An overview

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27120%2F22%3A10250360" target="_blank" >RIV/61989100:27120/22:10250360 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.worldscientific.com/doi/10.1142/S0218271822300099" target="_blank" >https://www.worldscientific.com/doi/10.1142/S0218271822300099</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1142/S0218271822300099" target="_blank" >10.1142/S0218271822300099</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Nonlocal gravity cosmology: An overview

Popis výsledku v původním jazyce

We discuss some main aspects of theories of gravity containing nonlocal terms in view of cosmological applications. In particular, we consider various extensions of general relativity based on geometrical invariants as f (R, square(-1) R), f (G, square(-1) G) and f (T, square(-1) T) gravity where R is the Ricci curvature scalar, G is the Gauss-Bonnet topological invariant, T the torsion scalar and the operator square(-1) gives rise to nonlocality. After selecting their functional form by using Noether symmetries, we find out exact solutions in a cosmological background. It is possible to reduce the dynamics of selected models and to find analytic solutions for the equations of motion. As a general feature of the approach, it is possible to address the accelerated expansion of the Hubble flow at various epochs, in particular the dark energy issues, by taking into account nonlocality corrections to the gravitational Lagrangian. On the other hand, it is possible to search for gravitational nonlocal effects also at astrophysical scales. In this perspective, we search for symmetries of f(R, square R-1) gravity also in a spherically symmetric background and constrain the free parameters, Specifically, by taking into account the S2 star orbiting around the Galactic Center SgrA*, it is possible to study how nonlocality affects stellar orbits around such a massive self-gravitating object.

Název v anglickém jazyce

Nonlocal gravity cosmology: An overview

Popis výsledku anglicky

We discuss some main aspects of theories of gravity containing nonlocal terms in view of cosmological applications. In particular, we consider various extensions of general relativity based on geometrical invariants as f (R, square(-1) R), f (G, square(-1) G) and f (T, square(-1) T) gravity where R is the Ricci curvature scalar, G is the Gauss-Bonnet topological invariant, T the torsion scalar and the operator square(-1) gives rise to nonlocality. After selecting their functional form by using Noether symmetries, we find out exact solutions in a cosmological background. It is possible to reduce the dynamics of selected models and to find analytic solutions for the equations of motion. As a general feature of the approach, it is possible to address the accelerated expansion of the Hubble flow at various epochs, in particular the dark energy issues, by taking into account nonlocality corrections to the gravitational Lagrangian. On the other hand, it is possible to search for gravitational nonlocal effects also at astrophysical scales. In this perspective, we search for symmetries of f(R, square R-1) gravity also in a spherically symmetric background and constrain the free parameters, Specifically, by taking into account the S2 star orbiting around the Galactic Center SgrA*, it is possible to study how nonlocality affects stellar orbits around such a massive self-gravitating object.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10300 - Physical sciences

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

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

Název periodika

International Journal of Modern Physics D

ISSN

0218-2718

e-ISSN

1793-6594

Svazek periodika

31

Číslo periodika v rámci svazku

06

Stát vydavatele periodika

SG - Singapurská republika

Počet stran výsledku

42

Strana od-do

"nestrankovano"

Kód UT WoS článku

000797247400001

EID výsledku v databázi Scopus

2-s2.0-85121581471