Constraining extended cosmologies with GW×LSS cross-correlations

Abstract

The rapid development of gravitational wave astronomy provides the unique opportunity of exploring the dynamics of the Universe using clustering properties of coalescing binary black hole mergers. Gravitational wave data, along with information coming from future galaxy surveys, have the potential of shedding light about many open questions in Cosmology, including those regarding the nature of dark matter and dark energy. In this work we explore which combination of gravitational wave and galaxy survey datasets are able to provide the best constraints both on modified gravity theories and on the nature of the very same binary black hole events. In particular, by using the public Boltzmann code Multi_CLASS, we compare cosmological constraints on popular ΛCDM extensions coming from gravitational waves alone and in conjunction with either deep and localized or wide and shallow galaxy surveys. We show that constraints on extensions of General Relativity will be at the same level of existing limits from gravitational waves alone or one order of magnitude better when galaxy surveys are included. Furthermore, cross-correlating both kind of galaxy survey with gravitational waves datasets will allow to confidently rule in or out primordial black holes as dark matter candidate in the majority of the allowed parameter space.

Complete analysis of the background and anisotropies of scalar-induced gravitational waves: primordial non-Gaussianity f NL and g NL considered

“…It is important to note that there are other cosmological sources of gravitational waves, such as inflation [108,115,[168][169][170], domain walls [171], first-order phase transitions [172][173][174][175][176][177][178], and preheating [179,180], which predict angular power spectra with a similar Cℓ ∼ ℓ −2 dependence as SIGWs. To distinguish SIGWs from these sources, cross-correlation studies between GWBs and various observables, such as CMB [108,112,153,154,[181][182][183][184][185][186], LSS [154,[187][188][189][190][191][192][193], and 21cm lines [194,195], have been proposed. Furthermore, it is worth mentioning that apart from the information JCAP06(2024)039 contained in the characteristic energy density Ωgw there is additional information embedded in the frequency dependence of C ℓ .…”

Signatures of primordial black holes in gravitational wave clustering

“…Our constraints are compared to current, tentative constraints coming from microlensing [111][112][113], accretion contributions to Galactic radio and X-ray emissions [114], CMB spectral distortions [80,115], 21cm signal [116]; dynamical constraints from dwarf galaxies [117,118], wide binaries [119]; NANOGRAV [120]; supernova lensing [121], Lyman-α [122], and LIGO GW data [123][124][125]. Other techniques have been used to forecast PBH constraints in a variety of mass ranges: e.g., [126] considers the combination of CMB distortions and the pulsar timing array measurements, [41] studies how the merger rate changes depending on the early and late abundances and gravity and dark energy models, while in [40] the high redshift merger rate is considered. Note that all these constraints are model-dependent as well; the ones based on GW measurements from binary mergers, in particular, share the same uncertainties our model has on EPBH and LPBH formation processes.…”

“…In parallel to the development of this work, another article investigated the potential of the cross-correlation between gravitational waves from binary black hole mergers and galaxy maps, in order to constrain modified gravity and dark energy models, and withing those theories, PBH abundance [41]. In that work, the authors focus on slightly different situations and use GW catalogs specifically generated; in the limits where the two analyses can overlap and be compared, the results agree and present a complementary point of view.…”

“…Even if, considering ABHs and PBHs having comparable masses (i.e., ∼ 5 − 100M ⊙ ,) the GW signal produced by their merger would be completely indistinguishable, surveys dominated either by ABHs or PBHs should have different merger rates [40] and show different tomographic angular power spectra. The work of [36] and other follow-up analyses [8,19,20,41] showed how the cross-correlation between GW and galaxy surveys changes depending on ABH/PBH relative abundance.…”

Cosmology and Astrophysics with Standard Sirens and Galaxy Catalogs in View of Future Gravitational Wave Observations

“…A more refined approach involves matching the spatial clustering of GWs and galaxies(Oguri 2016;Nair et al 2018;Bera et al 2020;Mukherjee et al 2020;Yu et al 2020;Libanore et al 2021;Mukherjee et al 2021;Cigarrán Díaz & Mukherjee 2022;Vijaykumar et al 2023b;Bosi et al 2023;Scelfo et al 2023).10 Available at https://github.com/CosmoStatGW/CHIMERA.…”