Dr. Turner's Notes: The History of Time Travel · 8:08pm Apr 1st, 2018
While there exist a great many stories written about time travel and its philosophical, theoretical, and social implications, very few have ever done any serious kind of research into how time travel actually works in reality. This is completely understandable, as traveling backwards in time is an extremely rare form of magic, to the point where most consider it impossible.
Before one can understand why time travel is so difficult, one must first have a basic understanding of the metaphysical structure of time itself. I have written about time streams in one of my previous entries, and how they form an infinite branching structure of multiverses across eternity. Time streams, as you might have already guessed from the name, are effectively rivers of time that flow from the past and into the future. Each time stream represents a multiverse in its entirety as its multi-dimensional space moves forward through the hyperdimensional reaches of reality.
There are two key takeaways from this. First, a timestream is always moving forward, never backward. Second, a timestream being in motion means that there exists a relative “location” in hyperdimensional existence for it to move to. The future, then, is by definition the part of hyperdimensional reality that the time stream is moving towards, but doesn’t yet exist in.
Both of these facts bear enormous implications on any implementations of time travel that may be carried out in practice. Firstly, it means that time-travelling to the future is, strictly speaking, impossible. You can’t travel to the future because the time stream itself has not yet moved to the future’s hyperdimensional location. To put it more simply, you can’t go to the future by time travel because the future doesn’t exist yet. The closest equivalent to futureward time-travel would be phasing, or removing something from reality in order to have it return a set amount of time later. In most practical cases it is indistinguishable from true time travel, but it is still an imperfect approximation, as there are some circumstances in which a phased-out object will find it impossible to return to reality. This, as my former mentor can attest, may result in tragedy.
Secondly, and perhaps more importantly, it means that traveling backwards through time is possible. However, because the flow of time is constantly moving forward, there are several obstacles posed to any prospective time traveler. If a time stream is like a river, then moving backwards through time is akin to swimming upstream: it requires a constant expenditure of energy. Eventually, anyone who’s traveled into the past will run out of energy needed to remain in the past, and will eventually be pushed by the constant forward-flow of time back to the present. This alone would make time travel restrictive enough, but it is additionally complicated by the fact that traveling backwards through the time stream exposes incredible destructive energies to any natural body, as well as to most forms of matter. For this reason, nearly anyone attempting raw time travel would be instantly annihilated by the effort, including most pre-mending planeswalkers.
Finally, there are temporal paradoxes — while little about the exact effects of temporal paradoxes is known, it has been proven that whenever a change is made to the time stream that alters the circumstances that enable said time travel to begin with, it creates stress on a plane’s fabric. This can lead to the appearance of time rifts, which in turn can threaten to erase an entire plane from history altogether. Any attempt at backwards time travel must be made with temporal paradoxes in mind, as causing the time stream to deviate from the past you remember can have catastrophic consequences.
The first being known to master the art of time travel was Urza. Though known to the few in Equestria that remember him as a tyrant, Urza’s ultimate goal was perhaps not too distinct from Harmony’s, even if he was far too cruel and tyrannical to wield Harmony’s power directly. His machinations to defeat Phyrexia eventually led him to explore time travel, but he quickly found that even a being as powerful as him could not survive a trip backwards in time. He then found that out of all materials, silver was the only one that showed resilience to the destructive temporal energies, and created Karn, the Silver Golem. Karn was able to travel backwards in time to further Urza’s plans, but due to the fears that it could create paradoxes, he was only allowed to make small changes to the timeline. Karn’s most successful attempt at a major timeline change was made during the Mending, when he traveled backward centuries to close a time rift.
Star Swirl was the second being known to have mastered time travel, though it was with far greater limitations. While he did not create a silver proxy to perform his time travel studies, he was able to weave his own time travel spell with several dozen layers of protective enchantments that shielded him from the temporal energies. To minimize the risk of paradoxes, as well as ensure that the spell had enough energy to make the trip with the enchantments intact, it came with a number of key restrictions. First, it could only be used to travel back in time a week, at most. Secondly, the spell could only be performed once by any single caster. Thirdly, and most importantly, the caster would only be allowed to remain in the past for a few moments before the spell ejected them forcibly to the present. This spell would later be altered by a unicorn named Starlight Glimmer, who very foolishly removed these restrictions, using the Cutie Map to harness Harmony’s magic to power the spell.
There is one final being that is known to have traveled back in time, though very little is known about them or how they managed to achieve it. My travels to alternate time streams have revealed that, in another history, a place known as Ugin’s Nexus may have been able to facilitate restrictionless time travel without paradoxes, allowing someone to change the entire history of the plane of Tarkir. Who that person was, how they managed to accomplish it, and how Ugin’s Nexus would resolve paradoxes in such a manner remain unknown to me, however.
– Time Turner, Ph.D.
Ugin for best Dragon. Say, will we get any info on ghost fire in your MLPlaneswaker stories? Cuz ghost fire's flavor text implies some humorous happenings.