According to the theory of General Relativity, spacetime is “curved”. A good way to visualise a “curved” space is to think of something like a sheet. If you put something heavy in the middle of the sheet on your bed, it will cave in around the weight, and you can see the curve in the sheet. There are lots of strange ways you can contort your sheet to give it a different curvature, and in the same way, physicists imagine different ways our universe could be contorted. One of the things that was come up with was the concept of a wormhole.
Keeping to our sheet analogy, a wormhole is what happens if you fold your sheet over in half, and then make a little tunnel from one side to the other side. Then, to get from one side of your sheet to the other side, you’d only need to go through this little tunnel, instead of having to traverse right across the sheet the long way around. As you might imagine, science fiction authors love the concept of wormholes, for this very reason.
On a more physical note, scientists have calculated what happens to wormholes, should they exist in our universe. It turns out that wormholes will vanish incredibly quickly – so quickly, in fact, that there is no time for anything to pass through. As far as we know it is impossible to hold open a large wormhole for a time long enough to travel through it. However, for microscopic wormholes, much smaller than an atom, there is a gap in our understanding and it is possible that such tiny wormholes might not disappear quickly. Alas however, they would in any case be too small for us to travel through. The other problem with wormholes is that we don’t know any way in which they can be created. This means that a. no new wormholes are being created, and b. if a wormhole did exist, it’s gone now. So, unfortunately, it looks like wormholes are relegated to remaining in the world of science fiction.
Postdoctoral Associate, Cornell University
Ph.D. Cornell University