Incompleteness Matters Not: Inference of $H_0$ from BBH-galaxy
  cross-correlations
  We show how the angular clustering between gravitational-wave standard sirens
and galaxies with known redshifts allows an inference of the Hubble constant,
regardless of whether the host galaxies of any of these sirens are present in
the galaxy catalog. We demonstrate this for the first time with realistic
simulations of gravitational-wave signals from binary black holes in a
three-detector network with Advanced LIGO and Advanced Virgo sensitivities. We
show that with such a network, the cross-correlation technique can be used to
infer the Hubble parameter with a precision of less than 10% (2%) at 90%
confidence with 50 (500) sources, even with a 100% incomplete catalog, which
does not contain the hosts of any of the gravitational-wave events. We compare
our method with the current state-of-the-art techniques used for the inference
of the Hubble parameter from real data. We argue that, if the clustering
information is not used explicitly, the inference of $H_0$ from real data is
expected to be prior-dominated.
