TY - JOUR

T1 - Constraints on cosmologically coupled black holes from gravitational wave observations and minimal formation mass

AU - Amendola, Luca

AU - Rodrigues, Davi C.

AU - Kumar, Sumit

AU - Quartin, Miguel

N1 - Funding Information: LA acknowledges support from DFG project 456622116. DCR thanks Heidelberg University for hospitality and support, he also acknowledges support from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq-Brazil) and Fundação de Amparo à Pesquisa e Inovação do Espírito Santo (FAPES-Brazil) (TO 1020/2022, 976/2022, 1081/2022). MQ is supported by the Brazilian research agencies FAPERJ, CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico), and CAPES. This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. We acknowledge support from the CAPES-DAAD bilateral project ‘Data Analysis and Model Testing in the Era of Precision Cosmology’.

PY - 2024/2

Y1 - 2024/2

N2 - We test the possibility that the black holes (BHs) detected by LIGO-Virgo-KAGRA (LVK) may be cosmologically coupled and grow in mass proportionally to the cosmological scale factor to some power k, which may also act as the dark energy source if k ≈ 3. This approach was proposed as an extension of Kerr BHs embedded in cosmological backgrounds and possibly without singularities or horizons. In our analysis, we develop and apply two methods to test these cosmologically coupled BHs (CCBHs) either with or without connection to dark energy. We consider different scenarios for the time between the binary BH formation and its merger, and we find that the standard log-uniform distribution yields weaker constraints than the CCBH-corrected case. Assuming that the minimum mass of a BH with stellar progenitor is 2 M☉, we estimate the probability that at least one BH among the observed ones had an initial mass below this threshold. We obtain these probabilities either directly from the observed data or by assuming the LVK power-law-plus-peak mass distribution. In the latter case, we find at 2σ level, that k < 2.1 for the standard log-uniform distribution, or k < 1.1 for the CCBH-corrected distribution. Slightly weaker bounds are obtained in the direct method. Considering the uncertainties on the nature of CCBHs, we also find that the required minimum CCBH mass value to eliminate the tensions for k = 3 should be lower than 0.5 M☉ (again at 2σ). Finally, we show that future observations have the potential to decisively confirm these bounds.

AB - We test the possibility that the black holes (BHs) detected by LIGO-Virgo-KAGRA (LVK) may be cosmologically coupled and grow in mass proportionally to the cosmological scale factor to some power k, which may also act as the dark energy source if k ≈ 3. This approach was proposed as an extension of Kerr BHs embedded in cosmological backgrounds and possibly without singularities or horizons. In our analysis, we develop and apply two methods to test these cosmologically coupled BHs (CCBHs) either with or without connection to dark energy. We consider different scenarios for the time between the binary BH formation and its merger, and we find that the standard log-uniform distribution yields weaker constraints than the CCBH-corrected case. Assuming that the minimum mass of a BH with stellar progenitor is 2 M☉, we estimate the probability that at least one BH among the observed ones had an initial mass below this threshold. We obtain these probabilities either directly from the observed data or by assuming the LVK power-law-plus-peak mass distribution. In the latter case, we find at 2σ level, that k < 2.1 for the standard log-uniform distribution, or k < 1.1 for the CCBH-corrected distribution. Slightly weaker bounds are obtained in the direct method. Considering the uncertainties on the nature of CCBHs, we also find that the required minimum CCBH mass value to eliminate the tensions for k = 3 should be lower than 0.5 M☉ (again at 2σ). Finally, we show that future observations have the potential to decisively confirm these bounds.

KW - black hole physics

KW - dark energy

KW - gravitational waves

UR - http://www.scopus.com/inward/record.url?scp=85184369963&partnerID=8YFLogxK

U2 - 10.48550/arXiv.2307.02474

DO - 10.48550/arXiv.2307.02474

M3 - Article

AN - SCOPUS:85184369963

VL - 528

SP - 2377

EP - 2390

JO - Monthly Notices of the Royal Astronomical Society

JF - Monthly Notices of the Royal Astronomical Society

SN - 0035-8711

IS - 2

ER -