A wormhole, also known as an Einstein-Rosen bridge, is a hypothetical topological feature that would fundamentally connect two separate points in spacetime. A wormhole is much like a tunnel with two mouths, one entering and one exiting. If the mouths were connected by a tube, then anyone who entered the first mouth would immediately emerge from the second. However, if the mouths were not connected by a tube but instead were warped so that their interiors touched each other, then someone could enter one mouth and exit through the other. This latter case is often referred to as a “shortcut” through spacetime.
Wormholes are thought to be possible due to the fact that spacetime can be warped and curved. In particular, it has been shown that under certain conditions, spacetime can fold in on itself so that two distant points become close together or even touch each other. If this happens, then it might be possible to create a wormhole connecting those two points.
There are many unanswered questions about wormholes including whether they are actually possible or whether they could ever be used for travel between different points in spacetime. Nevertheless, the idea of wormholes continues to fascinate scientists and laypeople alike and provides us with another way of thinking about the strange and wonderful nature of our universe.