Resolving the Hubble Constant Tension with Gravitational-Wave Dark Standard Sirens and the China Space Station Telescope

The Hubble constant (H0) tension remains a persistent challenge in cosmology. This discrepancy arises from the difference between the H0 value derived from the cosmic microwave background (CMB) and other cosmological probes, and the value obtained from direct measurements of nearby supernovae and cepheids. To address this tension, we investigate the potential of using gravitational-wave (GW) dark standard sirens as a new cosmological probe capable of providing an independent measurement of H0.

This talk presents a novel approach that combines the mock galaxy catalog from the forthcoming China Space Station Telescope (CSST) with simulated data from the next generation of ground-based GW detectors, such as the Einstein Telescope and Cosmic Explorer. By jointly analyzing the spatial distribution and redshift of the galaxies and the GW signals emitted by merging binary neutron stars, we demonstrate that the CSST-GW synergy can achieve a highly accurate determination of H0, with a precision of less than 1%.

Our study underscores the potential of multi-messenger cosmology to address fundamental questions about the nature of the universe and the laws of gravity, paving the way for future joint analyses of GW and electromagnetic data.