Wormholes are incredibly fascinating objects, but they are also completely hypothetical. We just don't know if they can really exist in our universe. However, new theoretical knowledge shows how we can possibly detect a wormhole – from a spray of high-energy particles that are emitted at the time of its formation.
It's easy to describe a wormhole. It's a tunnel through space that connects to distant points by a (hopefully) shorter route. In other words, it's the ultimate shortcut in nature. And while this type of setup is easy enough to write into the equations of general relativity (our current definitive understanding of gravity and how we uncovered the possible existence of wormholes), it is much harder to get working.
Over the decades, scientists have found a number of ways to construct real, actual wormholes. But every time they do, a little quirk of poorly understood physics comes in to ruin the party. For example, wormholes are fantastically unstable – once even a single photon travels down the neck, the entire wormhole rips apart at the speed of light, making it less useful for linking purposes.
Ultimately, to stabilize a wormhole, you need a source of negative mass – matter of negative weight. That doesn't seem possible, and so the theorists are kind of stuck.
In the meantime, however, it is possible to find wormholes, and a new paper in the preprint journal arXiv describes one possible technique.
This is how it works. Suppose a particle falls into a newly forming wormhole. If it has enough energy, it can spontaneously decay into two new particles. One of these particles can escape through the wormhole while the other can be reflected through the opening due to the strange physics in these tunnels.
Then a new particle enters the wormhole and collides with the reflected particle. The author of the work stated that this collision can reach any high energy. This means that what we see at our end of the wormhole could be a shower of high-energy radiation – an unmistakable burst of energy.
Now that we know that this type of particle shower is possible by opening wormholes, we can look around the universe to see if something fits the bill … and if we can travel to them.