Impacts of gravitational-wave standard siren observation of the Einstein Telescope on weighing neutrinos in cosmology

Abstract

We investigate the impacts of the gravitational-wave (GW) standard siren observation of the Einstein Telescope (ET) on constraining the total neutrino mass. We simulate 1000 GW events that would be observed by the ET in its 10-year observation by taking the standard ΛCDM cosmology as a fiducial model. We combine the simulated GW data with other cosmological observations including cosmic microwave background (CMB), baryon acoustic oscillations (BAO), and type Ia supernovae (SN). We consider three mass hierarchy cases for the neutrino mass, i.e., normal hierarchy (NH), inverted hierarchy (IH), and degenerate hierarchy (DH). Using Planck+BAO+SN, we obtain mν < 0.175 eV for the NH case, mν < 0.200 eV for the IH case, and mν < 0.136 eV for the DH case. After considering the GW data, i.e., using Planck+BAO+SN+GW, the constraint results become mν < 0.151 eV for the NH case, mν < 0.185 eV for the IH case, and mν < 0.122 eV for the DH case. We find that the GW data can help reduce the upper limits of mν by 13.7%, 7.5%, and 10.3% for the NH, IH, and DH cases, respectively. In addition, we find that the GW data can also help break the degeneracies between mν and other parameters. We show that the GW data of the ET could greatly improve the constraint accuracies of cosmological parameters.

Prospect for constraining holographic dark energy with gravitational wave standard sirens from the Einstein Telescope

“…However, since the GW standard sirens can break the degeneracy, the combination of CMB+BAO+SN+GW finally can give a 2% w measurement in the wCDM model. Actually, Wang et al [62] further showed that the future GW standard sirens observed by the ET can also improve the constraints on the neutrino mass by about 10%. For other relevant investigations, see, e.g., Refs.…”

Future constraints on dynamical dark-energy using gravitational-wave standard sirens

“…In this section we shall describe the method for simulating the Gravitational Waves Standard Sirens (GWSS) data, each data point of which consists of (z, d L (z), σ d L ) of a GW source, where d L (z) is the luminosity distance at the redshift z and σ d L is the associated error with d L (z). The constraining ability of this catalogue, together with other astronomical datasets, is further investigated in various cosmological models, for instance [56,57,60]. The simulation of GW data is model dependent, thus one needs to choose the fiducial values of model parameters.…”

“…Following some earlier works in this direction [56,57,60], the redshift distribution of the observable sources is given by…”

“…By roughly considering the mass distribution of the astrophysical objects NS and BH, we perform random sampling of their masses from uniform distributions U (M , 2M ) and U (3M , 10M ) respectively, with M being one solar mass. For more details, we refer to [57,60].…”

“…Here, considering these four well known dark energy parametrzations, namely, CPL, Logarithmic, JBP and BA, we perform a robust analysis by constraining their parameter space using the simulated GW data from the Einstein Telescope along with the standard astronomical probes such as cosmic microwave background radiation (CMB) [49,50], baryon acoustic oscillations (BAO) [51][52][53], Supernove Type Ia (SNIa) [54] and Hubble parameter measurements from the cosmic chronometers (CC) [55], in order to see how the data from GW improve the parameter space of these known parametrizations compared to their usual cosmological constraints availed from the known cosmological probes, CMB, BAO, SNIa and CC. We refer to some earlier works on dark energy with similar motivation, that means where the simulated GW data from the Einstein Telescope were taken into account [56][57][58][59][60][61]. We mention that it will be also interesting to use simulated GW data from other observatories like Laser Interferometer Space Antenna (LISA) [70], Deci-hertz Interferometer Gravitational wave Observatory (DECIGO) [71,72], TianQin [73].…”