Constraining the gravitational wave speed in the early Universe via gravitational Cherenkov radiation

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F25%3A00638042" target="_blank" >RIV/68378271:_____/25:00638042 - isvavai.cz</a>

Výsledek na webu

<a href="https://hdl.handle.net/11104/0375107" target="_blank" >https://hdl.handle.net/11104/0375107</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1475-7516/2025/07/088" target="_blank" >10.1088/1475-7516/2025/07/088</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Constraining the gravitational wave speed in the early Universe via gravitational Cherenkov radiation

Popis výsledku v původním jazyce

Scalar particles traveling faster than a subluminal gravitational wave generate gravitons via gravitational Cherenkov radiation. In this paper, we investigate graviton production by the primordial plasma within the framework of modified gravity in the early Universe, generating a relic graviton background. We find that for the minimal model, where only the speed of gravitational waves is modified and a standard model plasma minimally couples to gravity, the relic graviton background can be enhanced by several orders of magnitude, but still agrees with the Big Bang Nucleosynthesis (BBN) bound. Moreover, we also find that for Horndeski theories, such as Galileon theory, the relic background produced by the thermalized scalar field can reach significant amplitudes, exceeding the BBN bound for a region of the parameter space. By requiring the relic graviton background to remain consistent with the BBN constraint, we derive limits on the gravitational wave speed at early times in these modified gravity theories.

Název v anglickém jazyce

Constraining the gravitational wave speed in the early Universe via gravitational Cherenkov radiation

Popis výsledku anglicky

Scalar particles traveling faster than a subluminal gravitational wave generate gravitons via gravitational Cherenkov radiation. In this paper, we investigate graviton production by the primordial plasma within the framework of modified gravity in the early Universe, generating a relic graviton background. We find that for the minimal model, where only the speed of gravitational waves is modified and a standard model plasma minimally couples to gravity, the relic graviton background can be enhanced by several orders of magnitude, but still agrees with the Big Bang Nucleosynthesis (BBN) bound. Moreover, we also find that for Horndeski theories, such as Galileon theory, the relic background produced by the thermalized scalar field can reach significant amplitudes, exceeding the BBN bound for a region of the parameter space. By requiring the relic graviton background to remain consistent with the BBN constraint, we derive limits on the gravitational wave speed at early times in these modified gravity theories.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10303 - Particles and field physics

Projekt

<a href="/cs/project/LUC23115" target="_blank" >LUC23115: Spin 2 WISPers z laboratoře do vesmíru</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2025

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

1475-7516

Svazek periodika

2025

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

18

Strana od-do

088

Kód UT WoS článku

001542424800001

EID výsledku v databázi Scopus

2-s2.0-105011989604