Speaker
Description
Galaxy surveys have traditionally served as the primary probe of the large-scale structure (LSS) of the Universe. The rapidly growing catalog of gravitational-wave (GW) merger events now offers an independent and complementary probe for cosmological studies. Third-generation (3G) GW observatories, including the Cosmic Explorer and Einstein Telescope, are expected to detect thousands of compact binary mergers per year with localization areas smaller than a square degree. Concurrently, next-generation electromagnetic surveys, such as the Vera C. Rubin Observatory and the Square Kilometer Array, will provide unprecedented maps of cosmic structure. We present new statistical methods for using GW observations to probe the background cosmology and the LSS of the Universe, and discuss strategies for combining GW merger catalogs with galaxy survey data. We show that 3G detectors can independently probe key LSS observables, including baryon acoustic oscillations (BAO) and clustering bias, using GW observations alone. Furthermore, studying the redshift evolution of these LSS features may provide new insights into the connection between compact binary formation and cosmological structure formation.