I doubt that time travel could ever really happen. But some scientists like to ponder it, and I agree it can be interesting to think about. There are many paradoxes that it creates. A new hypothesis is that if time travel ever gets invented, that it would create its own destruction by introducing instability into certain realities which would eventually lead to the most stable possible timeline — that is, one without time travel at all.

It’s true that time travel would definitely create instabilities. People would go through history and wreck it, whether for their personal gain or just for fun or to be malicious or even without trying to. Facts and historical events would get altered, which would change the future. But with multiple people changing the past, they could create a future that cannot exist due to being incompatible with itself. The universe automatically makes things be in balance. We’ve defined this as the laws of thermodynamics. Objects will return to their most stable state, to keep equilibrium. So by that reasoning, it’s possible that even if time travel were to exist, it might lead to a future where it cannot exist. That leads to a paradox which might make your brain hurt if you try to understand it. 🙂 If it removed itself, would we forget about it and keep reinventing it? Wouldn’t that cause some distortions in the time-space continuum? What if someone somehow created a future that required time travel to exist? Would our universe just go poof?

BTW, the article linked above is called “Where Are All the Tourists From 3025?”, which seems like a good title for a book…

Bonus: Time travel becoming confusing reminds me of several episodes of Milo Murphy’s Law, which is an awesome show if you don’t know. Don’t think it’s just a kid’s show because it’s animated. It’s clean and family-friendly, but hilarious and full of parody references and inside jokes. And the lead character is voiced by Weird Al Yankovic, who does a great job with it. Part of an ongoing side story in the show involves two time travelers, who see a lot of clocks in the timestream. One of them says the clocks was probably someone’s idea of a joke. I don’t want to spoil it, because it’s fun to see how it all plays out, but if you just want to know without watching, click here and look for “Floating Clocks” (which is a common trope for showing that time travel is happening, and here they explain it… kind of). Or, if you want to see just that clip: Clocks in the timestream. (It’s a weird clip to start with though, because most episodes are more realistic and don’t involve alien pistachios.) There’s another time travel paradox in this episode involving a letter someone put in the past for their future self. (Think about that one.) There’s also a peach paradox in the show, and there’s a video clip of it on that page.

Anyway, that’s a lot of rambling about time travel, but you also got a show recommendation. I think it’s laugh-out-loud funny, and my kids like it, too. (It was created by the same guys who created Phineas and Ferb, which is another great show I recommend.)