Both electrically charged black holes and their rotating cousins share one curious property: they automatically, without any hesitation or flinching, create a wormhole. What’s better, these wormholes work way better than their more straightforward relatives described earlier. There’s still a white hole anchored to the black hole by their singularities, but in this case you can enter the event horizon of the black hole, travel near the singularity without getting swallowed by it, and find yourself expelled out the white hole in another universe.
