  The first direct observation of gravitational waves' action upon matter has
recently been reported by the BICEP2 experiment. Advanced ground-based
gravitational-wave detectors are being installed. They will soon be
commissioned, and then begin searches for high-frequency gravitational waves at
a sensitivity level that is widely expected to reach events involving compact
objects like stellar mass black holes and neutron stars. Pulsar timing arrays
continue to improve the bounds on gravitational waves at nanohertz frequencies,
and may detect a signal on roughly the same timescale as ground-based
detectors. The science case for space-based interferometers targeting
millihertz sources is very strong. The decade of gravitational-wave discovery
is poised to begin. In this writeup of a talk given at the 2013 TAUP
conference, we will briefly review the physics of gravitational waves and
gravitational-wave detectors, and then discuss the promise of these
measurements for making cosmological measurements in the near future.
