Some supermassive black holes at the centre of galaxies may actually be wormholes that link two distant parts of the universe together, astrophysicists suggest.
In his Theory of General Relativity, Albert Einstein predicted the existence of wormholes, which connect two points in space or time, but they have yet to be discovered.
Now experts from the Central Astronomical Observatory in Russia believe the 'black holes' at the centre of some very bright galaxies (known as the active galactic nuclei or AGNs) could be the entrances to these wormholes.