Mysteriously quiet space baffles researchers (Synopsis) [Starts With A Bang]

We live in a Universe full of galaxies, supermassive black holes, and violence. The violence is particularly relevant here, because every so often, these galaxies merge, and if they each contain a supermassive black hole, the gravitational wave “ripples” that get sent through space will literally shake and affect everything that’s in them.

If you had a perfect clock — something that kept time perfectly that you could watch “tick” — you’d expect to see the timing of these ticks be affected. Astrophysics gives us these clocks: millisecond pulsars, in great abundance. Yet the Parkes Pulsar Timing Array project has just completed an 11-year survey of thousands of them, and found no evidence of the gravitational waves they were expecting.

What gives? Is there new physics? Do we have the merger scenarios all wrong? Or is gravity, general relativity and gravitational wave theory all wrong?

Sabine Hossenfelder doesn’t have the answer, but she has the evidence, the mystery and the possibilities for you over on Starts With A Bang!