Unusual Gravitational Wave May Be Sign of Wormhole Linking Universes

In 2019, LIGO and Virgo recorded something truly bizarre – a gravitational wave event less than a tenth of a second in duration.

Compared to the drawn-out chirps of black hole binaries on decaying orbital spirals, it was a sharp crack. The best explanation of the event, named GW190521, was a chance encounter of two black holes snaring each other in passing.

Now, a new paper has presented an alternative, far more exotic option: the echo of a black hole collision in another universe, reverberating through a collapsing wormhole that formed as a result of that merger.

Related: Two Black Holes Met by Chance, And It Created Something Never Seen Before

To be clear, the black hole collision right here in our own Universe is still the preferred interpretation of the strange signal… b