Everyone talks about how they’d kill Hitler. It doesn’t work that way. It happened. He’s already dead. You all are. 

We can go back and see him. We can immerse in the zeitgeist of the time and you can bring back precise, objective knowledge. The grandfather paradox, is real. Best you can do is fork the timeline. You then move on in a timeline with no Hitler, but the original timeline, the one you came from, the prime line, still exists and he is still part of it.

Other people think they’ll go back and discover electricity or invent the car. You can’t do that either. You can’t, because you didn’t. The loop paradox is real, too. 

I’ll tell you how it works.

First, there were the out and backs. We send a team out. Way, way out into space. Your theories on relativity and spacetime were correct. They return and a few hundred years has passed and they can report to us what it was really like in their time. 

Traveling to the future is easy. There are no paradoxes. It is really time travel in name only, though. It served a purpose, applying the scientific method to history, which suffers from retro bias. Your Orwell had it right when he said “he who controls the past, controls the future.” Histoty is subject and requires context and perspective. Still, we were surprised that it was not the out and backs who were flummoxed by the changes they saw in the time they were gone. Many technical innovations had long been posited in fiction and had come to fruition or were merely a more advanced version of what existed in their time. What happened was the inverse. 

The out and backs were grilled for their insights into their time. The anthropologists wanted to know if what they hypothesized about global dynamics of the time was right. The sociologists wanted to know what it felt like. The economists wanted to know what unchecked capitalism meant to their day to day lives and how markets became susceptible to a single social media post. 

The inversion of this objective is what really paved the way for time travel to the past. Or the approximation of it in what is known to us as the Facsimulacrum. You are no doubt aware of the work of Einstein, we understand he was quite known in your time. So you may well have heard of some of his theories, whether you truly reckoned with the impact of them, but he was the bridge between classic physics and the idea that time is linear and quantum mechanics, where space time are vectors on the same dimension and form more of a tapestry, than a single, immutable line that runs off into infinity. 

Still, the assumption was that it could be bent, but still moved in one direction. Gravity, for example seemed to have the power to slow or accelerate its passage. The scientists of your era, built on that and theorized that everything is a particle or a wave. That’s not true, but it got them to the next step. Wave function and amplitude.

If I were to tell you the location of every object, of every size in the universe and everything about it. Its mass, location, velocity; you could predict with high probability where it came from and where it was going. Taken to the logical extreme, this would allow you to predict the future. If that’s true, given enough information, you could look very far back. Deep time. 

This is from where, in the parlance of your time, terms like the Butterfly Effect were derived. A butterfly flutters its wings and a hundred years later, that wind is now a hurricane. Beyond that is the understanding that something set that butterfly in motion as well. Seemingly random events, are merely unexpected because you don’t know all the variables, you can never know them all. Still, all of this led to the confidence to try the theories at least at a foundation with those first out and backs. But for the foresight to keep sending them, we would have reached the epiphanies sooner.

It wasn’t until centuries had passed and we realized that not only were these travelers useful for historical and social sciences, but for science. They helped us assemble that measure of the wave function I told you about. The amplitude. Much like your more advances algorithmists would look at prior data to predict an outcome for a stock purchase or make shopping recommendations, we could assemble data from periods before we knew what to collect, string it through to now—my now, not your now—and see where everything was headed. Everything. From natural disasters to the outcome of sporting events to the moon cracking open to a butterfly flapping its wings. So we started sending the out and backs further away, for longer and with the right tools and information to collect exactly what we needed to feed the data into the system, to make it more and more accurate and prescient. 

The breakthrough was that we eventually could project backward as well. Well enough that we could fully assemble the entire universe in the Facsimulacrum and visit it. At any point in history. So even if we come back with intent to kill Hitler, and we certainly considered it as surely as you are now, it wouldn’t matter. A new instance would be respawned, and we don’t know what happens in it. We can’t enter it. We don’t know enough about it now, because the field has been disrupted and altered. 

You ask for our help, but we can’t give it. It is against the code to interfere and also fruitless. This is real to you, because we have perfectly assembled the field state in which you exist as a conscious participant. In all likelihood you exist on the prime line. Or you did. We call it the allegory of the cave man. Another of your stand out, foundational thinkers was Plato, no? He talked of the impossibility of an enlightened thinker, being able to enlighten by proxy from their own experience. Explaining a universe—truly a multiverse—of wonder to someone who had only ever seen shadows dancing on a wall. You have your cavemen. And if you were to go back, what could you teach them that would change the fact that they are tens of thousands of years behind you. And dead. Would you give them fire? The wheel? Potable water? Do you think you could figure out the greatest villain of their time and eliminate them?

Would you bother trying to teach these violent, hairy, naked apes? 

So it went for millenia, until one day one of the out and backs went far enough to be pulled from our ability to control or monitor and disappeared. We knew nothing of where, and other than the disappointment in our formulas to predict such an outcome, we accepted this as one of the possible outcomes. We know now. 

They were pulled toward a black hole. They fell toward it with ever increasing velocity that most of the crew were killed by the pressure. All but one. She survived. We know she survived, because she made it back to now. Your now, this time, not my now. I don’t mean within this simulation, I mean on the prime line. We know this because she continued her mission and has sent us information that only could have been left by her, for us. 

I know you are thinking that I told you that wasn’t possible. There are countless paradoxes that preclude it. However, if space time is a fabric, it can be folded upon itself. The paradoxes don’t always apply, for example, you can’t go back in time, because it meant you have already gone back in time, and that would create an infinite loop.

Except it didn’t because it only happened once, on the prime line and she is aware that she must not do anything that disrupts the prime line. If she doesn’t remain statelessly aware of the wave function, she can cause the ripple that means she never existed. The best possible outcome is that we keep searching for each other, as she ducks the paradox; a prisoner hiding notes in the cracks of the wall. She will think she is successful as long as she exists. We can never send messages back, we can only act on hers. We, likewise, think that she is successful as long as we exist. 

What we can never truly know, is if we exist at all, or we, ourselves are part of the illusion.  Trapped, ourselves, in the Facsimulacrum. Entangled. Catching glimpses of the horizon from the wave tops of the churning oceans of time.