Neutron stars as gravitational wave emitters and detectors

In this thesis, we explore the duality of neutron stars in our Galaxy as both the sources of gravitational waves, perturbations of space-time propagating with the speed of light, and the nature-built detectors for gravitational waves from coalescing supermassive black holes in far-away galaxies, known as pulsar timing arrays. We develop new methods to search for gravitational waves from neutron stars. We also characterize the pulsar timing array noise that is known to originate from neutron star interiors. Moreover, we find new sources of noise in pulsar timing arrays and we develop new techniques to better understand the data.