In the last year, scientists detected gravitational waves – ripples in space time – when it was believed that two black holes collided and subsequently merged.
But now experts are questioning whether black holes were the source of the gravitational waves, or rather worm holes.
Black holes have never been directly observed but by the way space acts around them, scientists have been able to determine that they probably do exist.
However, there is no evidence to suggest that worm holes are nothing more than a theory which belongs in the realms of science fiction.
This is why scientists are considering whether they can use gravitational waves to detect worm holes.
The issue the experts have with black holes is they have an event horizon – a boundary around black holes where nothing, not even light, can escape, so surely gravitational waves would not be able to escape the reaches of black holes?
Wormholes could be the answer, according to research from a Belgian university, which would suggest that black holes don’t exist altogether and it could be another type of exotic compact object (ECO).
Pablo Bueno from KU Leuven University said: “Wormholes do not have an event horizon, but act as a space-time shortcut that can be traversed, a kind of very long throat that takes us to another universe.
“The confirmation of echoes in the LIGO or Virgo signals would be a practically irrefutable proof that astrophysical black holes don’t exist.
“Time will tell if these echoes exist or not. If the result were positive, it would be one of the greatest discoveries in the history of physics.”
Mr Bueno and his colleague Pablo Cano add: “The final part of the gravitational signal detected by these two detectors – what is known as ringdown – corresponds to the last stage of the collision of two black holes, and has the property of completely extinguishing after a short period of time due to the presence of the event horizon.
“However, if there were no horizon, those oscillations would not disappear completely; instead, after a certain time, they would produce a series of ‘echoes,’ similar to what happens with sound in a well.
“Interestingly, if instead of black holes, we had an ECO, the ringdown could be similar, so we need to determine the presence or absence of the echoes to distinguish the two types of objects.”