Sascha Husa
Lecturer of Theoretical Physics at the University of the Balearic Islands and member of the Relativity and Gravitation group, which is part of the LIGO and GEO consortia and the e-LISA and Einstein Telescope projects
It is a revolutionary finding in the sense that the Pulsar Timing [PTA] method is proven to be able to detect signals. The sensitivity of this method will slowly increase and it is hoped that, at some point in the future, we will be able to learn more about the sources of these signals.
The big difference with LIGO and other observatories such as LISA or the Einstein Telescope is that with these we detect individual signals and not just a stochastic background. In addition, it is already possible to identify the sources of the signals observed with LIGO and LISA, and to learn directly about astrophysics, cosmology and fundamental physics. With Pulsar Timing this phase of learning about astrophysics and other areas will take more time, but the fact that very low frequencies, and thus new aspects of physics, can be observed is very exciting.