Where is Love? Tidal deformability in the black hole compactness limit

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F47813059%3A19630%2F20%3AA0000064" target="_blank" >RIV/47813059:19630/20:A0000064 - isvavai.cz</a>

Výsledek na webu

<a href="https://iopscience.iop.org/article/10.1088/1361-6382/abb07a" target="_blank" >https://iopscience.iop.org/article/10.1088/1361-6382/abb07a</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1361-6382/abb07a" target="_blank" >10.1088/1361-6382/abb07a</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Where is Love? Tidal deformability in the black hole compactness limit

Popis výsledku v původním jazyce

One of the macroscopically measurable effects of gravity is the tidal deformability of astrophysical objects, which can be quantified by their tidal Love numbers. For planets and stars, these numbers measure the resistance of their material against the tidal forces, and the resulting contribution to their gravitational multipole moments. According to general relativity, nonrotating deformed black holes, instead, show no addition to their gravitational multipole moments, and all of their Love numbers are zero. In this paper we explore different configurations of nonrotating compact and ultracompact stars to bridge the compactness gap between black holes and neutron stars and calculate their Love number k(2). We calculate k(2) for the first time for uniform density ultracompact stars with mass M and radius R beyond the Buchdahl limit (compactness M/R &gt; 4/9), and we find that k(2) -&gt; 0(+) as M/R -&gt; 1/2, i.e., the Schwarzschild black hole limit. Our results provide insight on the zero tidal deformability limit and we use current constraints on the binary tidal deformability (Lambda) over tilde from GW170817 (and future upper limits from binary black hole mergers) to propose tests of alternative models.

Název v anglickém jazyce

Where is Love? Tidal deformability in the black hole compactness limit

Popis výsledku anglicky

One of the macroscopically measurable effects of gravity is the tidal deformability of astrophysical objects, which can be quantified by their tidal Love numbers. For planets and stars, these numbers measure the resistance of their material against the tidal forces, and the resulting contribution to their gravitational multipole moments. According to general relativity, nonrotating deformed black holes, instead, show no addition to their gravitational multipole moments, and all of their Love numbers are zero. In this paper we explore different configurations of nonrotating compact and ultracompact stars to bridge the compactness gap between black holes and neutron stars and calculate their Love number k(2). We calculate k(2) for the first time for uniform density ultracompact stars with mass M and radius R beyond the Buchdahl limit (compactness M/R &gt; 4/9), and we find that k(2) -&gt; 0(+) as M/R -&gt; 1/2, i.e., the Schwarzschild black hole limit. Our results provide insight on the zero tidal deformability limit and we use current constraints on the binary tidal deformability (Lambda) over tilde from GW170817 (and future upper limits from binary black hole mergers) to propose tests of alternative models.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Classical and Quantum Gravity

ISSN

0264-9381

e-ISSN

1361-6382

Svazek periodika

37

Číslo periodika v rámci svazku

19

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

15

Strana od-do

„195017-1“-„195017-15“

Kód UT WoS článku

000570861000001

EID výsledku v databázi Scopus

2-s2.0-85091948522