Some scientists believe a signal detected by gravitational wave observatories in 2019 may have originated from a parallel universe. The event, named GW190521, was recorded by the LIGO and Virgo detectors and lasted less than a tenth of a second, described as a sharp crack rather than the typical chirp of black hole mergers.
A team led by Dr Qi Lai of the University of Chinese Academy of Sciences has proposed that the signal could be an echo from a collapsing wormhole linking our universe to another. In a pre-print paper, they suggest the ringdown from binary black holes merging in another universe might pass through a wormhole's throat and be detected here as a short pulse.
While the preferred explanation remains a black hole collision, the researchers argue that the wormhole scenario cannot be entirely ruled out. The abrupt end of the signal could be explained by the wormhole being open only briefly. Dr Lai noted that the wormhole could connect two separate universes or distant regions within a single universe.
If confirmed, the theory would provide evidence for the existence of wormholes and offer a new tool for studying them. However, the scientific community generally views the parallel universe hypothesis as speculative, with the black hole collision interpretation being far more likely.
