What If You Prevented Your Own Death Through Time Travel? | Unveiled

What if You Prevented Your Own Death Through Time Travel?

There’s a reason why time travel is still one of the most enticing, exciting and mysterious sci-fi concepts around; it allows for almost endless possibilities. However, though life is certainly unpredictable, one aspect of it seemingly isn’t - the fact that everything that lives will one day die. In an alternate reality or a far-future time, though, could the most advanced temporal technology change even this?

This is Unveiled, and today we’re answering the extraordinary question; what if you prevented your own death through time travel?

From the beginning, there are some problems with today’s time-turning thought experiment… the first and biggest of which being that you don’t know when you’re going to die until it happens. And after it happens, well, you’re dead, and unable to use any kind of time machine to go back and avert your fate. Luckily, though, if you were living in a time or place where time travel already exists, then somebody else could feasibly provide you with the knowledge you’d need – the precise moment and location at which your life ends - because they might’ve already travelled to that point. Naturally, they’d have to also be someone you deemed extremely trustworthy, because your life would very much be in their hands and under their control.

In terms of how it would work, theoretically speaking, time-travel to the future is relatively simple… all you have to do is go fast enough. Thanks to time dilation, the faster you go relative to something else, the further into the future you travel. But the issue is made a lot more complicated when traveling back to the past. And, while you’d be going to the future to stop your own death, whoever had provided you with the information on where to go would have had to have either seen the future by some other means… or come from the future themselves. So, backwards time travel is as important as forwards, for this particular mission.

The encouraging news is that time travel to the past might not be impossible in models of general relativity. According to some theories, it could hypothetically be done by your going close enough to a massive enough black hole, for example. Or by you somehow exceeding the speed of light. Whether or not those will ever be viable options, or indeed whether they’d ever actually work, is another matter… At best, preventing your own death via time travel would take a lot of time, energy and effort. First, someone goes back in time to assist; then you fly to your future; and then you find and get to a black hole to slingshot yourself back to your original time. Even if it was possible, to today’s mind it’s not exactly practical.

Philosophy offers a different perspective on this physical conundrum, though. Fatalism and determinism are two similar (though not identical) schools of thought which suggest that you can’t change the future. Whatever happens. In fatalism, humans are only free to do what they actually do. This means that if you’re debating whether to have cereal or toast for breakfast, for example, and you choose cereal, you were always going to pick cereal. You both do and don’t have a choice, but you couldn’t go back and change that choice because everything only happens one way; the cereal way. Determinism similarly opposes free will and suggests that there is no way to avert future events when talking about time travel, because they are pre-determined. So, in the case of today’s question, it doesn’t matter whether forward or backwards time travel is ever possible, because you can’t prevent your own death, simply because it’s your death. Unless, of course, you were always meant to time travel and prevent your own death - at which point, you’re not actually preventing anything that wouldn’t have happened anyway. The fatalistic arguments are full of these neat, full-circle inevitabilities.

But there are ways and theories to get around a fatalistic model, too… namely parallel universes and alternate timelines. Here, though you may only ever be able to have cereal for breakfast in this universe, that choice spawns numerous parallel worlds – including worlds where you have toast, toast and cereal, or one where you just skip breakfast entirely. We can’t currently prove that parallel universes exist, but this also doesn’t mean that they don’t - we can’t disprove them, either. And, when you imagine achievable time travel into the scenario, too, well, reality really starts to splinter.

One interpretation of parallel worlds, for example, could be that in one universe you are going to die at a certain time and at a certain place and you can’t change that… but, then, by time-travelling to try and change it, you actually create a whole new universe to inhabit; starting an alternate timeline in a separate existence. And, maybe, if your mission is successful, in that universe you don’t die there or then, but at a different point entirely. It doesn’t offer a great deal of comfort to the version of you in the original universe - because they still die - but it does open up a whole new dimension of death-defying possibilities, quite literally.

If your priority remains simply to stop your own death in this particular universe, though, there are probably better, more efficient ways to go about it. In a hypothetical future where time travel technology both exists and is accessible enough for you to even entertain this dream, it’s perhaps not unreasonable to expect that there are other pieces of tech on the horizon to make your mission easier, too - like ones aimed at prolonging life in general. Perhaps you could time travel to a point long past your death to learn the details of things like AI preservation, cryonic freezing or reverse aging - things that might not have been around in your own lifetime. But then you could bring that knowledge back to your own timeline, apply it to yourself, and miraculously live on. It’s much more indirect, but it is another scenario where time travel saves your life. Unless, of course, fatalism rings true, again, and you were always meant to do all of that anyway… in which case, it’s hopeless from the outset.

Finally, though, say all of these currently impossible things came to pass; forward time travel was possible, backwards time travel was possible, you were able to learn when and where you were going to die and you were able to change the future to prevent it… even after all that, you’ve got problems in the shape of paradoxes. One of the biggest and most mind-boggling issues is that once you go forward in time to prevent your own death, you remove the motivation to go forward in time and prevent your death in the first place. Because, why stop what doesn’t need stopping… because it’s already been stopped? Why worry about something that doesn’t happen, even though it only doesn’t happen because you worried about it to begin with? In this scenario, the vital information about where and when you’ll die immediately becomes incorrect or just wouldn’t exist at all… which means you would never have gone to the future, to set the events in motion. The whole episode is erased.

In other circumstances, you could also inadvertently create a self-fulfilling time loop… when by going to the future to prevent your own death you actually accidentally ensure that you’re going to die. What if you die getting struck by a car, so you travel to the future to stop it? Then, what if you as the time traveller are somehow the cause for the “original timeline you” getting hit? If you’d never have messed with time, it would never have happened! Or, what if in trying to stop it, you get hit by the car and killed as the time traveller? You will have actually cut shorter your original timeline, in your misguided efforts to save your own life!

It’s clear, then, that time travel is a complicated business, and it only gets more so when you start attempting to change predetermined events, or to jump across parallel universes to find the one you like best. It’s a sobering thought, but even if we could bend and shape spacetime to our will, perhaps we will never be able to avoid this one inevitably fixed point. You might shift it, or tweak it, but you couldn’t outrun it… and in the meantime, there’s an endless web of paradoxes to contend with. And that’s what would happen if you prevented your own death through time travel.