When two neutron stars slammed together far off in space, they created a powerful shaking in the universe — and their echoes could violate Einstein's theory of relativity.
Black holes shouldn't echo, but this one might. Score 1 for Stephen Hawking? : Read more
"But in the 1970s, Stephen Hawking wrote a series of papers suggesting that the borders of black holes
aren't quite so smooth. Instead, they blur thanks to a series of effects linked to
quantum mechanics that allow "Hawking radiation" to escape. In the years since, a number of alternative black hole models have emerged, where those smooth, perfect event horizons would be replaced with flimsier, fuzzier membranes."
Looks like efforts to test quantum gravity here, something critical to inflation and multiverse doctrine in the Big Bang model.