Could black holes be portals to other universes?

There is a long history to the idea that black holes may connect with other regions of the Universe, or other universes entirely, but this is purely speculation.


Asked by: Stuart Laws, by email

Some physicists have attempted to combine quantum mechanics with the General Theory of Relativity and concluded that black holes may not contain a ‘singularity’, the point at which density becomes infinite. This would open up the possibility that black holes are shortcuts to other universes. Actual tunnels through space-time, called ‘wormholes’, may be a better bet for traversing between universes. But although they’re predicted by Einstein’s theories, no wormholes have yet been discovered, and there are doubts that they could occur naturally at all.

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