Research Division Seminar
A robust cosmic standard ruler from the cross-correlation of galaxies and dark sirens

Resumen

Dark sirens are sources of gravitational waves (typically mergers of black hole binaries) without an electromagnetic counterpart. The gravitational waveform measured by our detectors allows us to infer the distance (not the redshift) to those sources, and with the new generation of detectors such as the Einstein Telescope, the uncertainty in their angular position and distance will decrease dramatically. In this talk I will show that by correlating dark sirens and galaxies we can directly draw the Hubble redshift-distance relation, with minimal assumptions about the underlying cosmology. This allows for a direct measurement of the Hubble parameter, free of the systematics of standard sirens and without the model dependence of the Planck constraint, which can achieve an accuracy of 4% with run 5 of the LIGO-Virgo-Kagra network of gravitational wave detectors, and less than 1% with the future facility Einstein Telescope.