the trouble with wormholes
Wormholes exist, but they may be impractical for travel according to what we know about the physics behind them.
Unless you resolutely refuse to read anything about science fiction of ideas about traveling to alien worlds around other stars, you're probably familiar with the concept of a wormhole. But just in case, here's a quick and dirty review of the basics behind the theory.
Right now, wormholes on a macro scale are purely theoretical. It's not a big deal really. Until recently, black holes were just a bizarre set of formulas buried deep in the framework of general relativity. When we built the right tools, we found that these objects are actually swarming our universe like weeds in an abandoned garden. The same could happen with wormholes in the next few decades. However, even if we find vast networks of these strange shortcuts through space and time permeating the cosmos, the closest one might be thousands of light years away and do us absolutely no good when it comes to interstellar travel. To exploit wormholes for exploring the outer reaches of the galaxy and beyond, we'll need to learn how to make them.
Of course this is easier said than done. We'd need to learn not only how to punch a hole in space, but how to stream enough energy down its throat to keep the wormhole from collapsing. More than that, we'd need to know how to make it connect with a section of space-time hundreds of trillions of miles away to provide the necessary shortcut. There's also the issue of how big its mouth would have to be since it would have an event horizon with tidal forces that could rip a poorly aimed spacecraft to shreds.
Finally, there's the issue of potential time travel which would invoke all sorts of paradoxes. If, as in the example in the video, you went back in time with five years worth of stock performance charts to make yourself rich, could you really change history? And what would happen to you as you're transported in time? Could some unforeseen effect change your biological age? Or could the bizarre conditions in the wormhole itself trigger a storm of Hawking radiation and roast your craft to a crisp no matter how you try to travel through it?
As much as I'd like to provide some sort of answer to these questions, so far, we only have conceptual guesses. Until we can experiment with wormholes on scales larger than subatomic, or find an actual pathway through space-time, math and very elaborate conjecture are all we have…
