Unless something has changed we’ve basically confirmed gravitational waves. “We” being the human race, I wasn’t actually personally involved. The way they were discovered is super neat to me. Like most good science, it involved lasers. Basically they built an array that sends light through (And off) a mirror at 45 degrees. Both beams pass a distance before hitting another mirror and then reflecting back. If the system is working properly, calibrated and whatnot, the two beams will cancel on another out and no light will enter a sensor in the system.
But if something were to alter the space between the mirrors this would alter the distance between the reflectors and cause the waves to be out of sync (the likelihood of the difference being so perfect that both would still cancel one another out seems unlikely, perhaps mathematically impossible).
At any rate, the only thing that could really cause this to happen (globally mind, they have these stations all over the world) would be gravitational waves. I won’t act like I full get it, but my understanding is that these are literal waves of space that compress and expand, just like waves in a bath. Even the tiniest wave, felt across the world, would be enough to offset the beams and trigger the sensors.
This is super neat to me. I recall a while back the idea of a warp drive that would do something similar, basically warping space ahead of the ship and behind it to ride a “wave” of distorted space. It still seems unlikely that anything like that will come from this in the near (or even distant) future it is certainly nice to know that it isn’t entirely fantasy.