It's a way of "seeing" (or "hearing"...both work) the universe in clearer ways and deeper into it's past. (The farther out you can "see," the earlier into the universe's origins you are "seeing.") gravity waves--predicted by Einstein--are a way of doing just that. It brings us closer to the Big Bang--but I'm afraid still not how things were before it.
Most of everything may be inside all those black holes. Dark matter may just be a bunch of ancient black holes - Tech Insider
gravitational waves - what it means https://www.washingtonpost.com/news/speaking-of-science/wp/2017/10/17/what-the-new-gravitational-waves-discovery-means-for-the-future-of-astronomy/?utm_term=.52318ff74ff2
