Free Time Agency by Aaron Frale

near to this time stream. Technology seemed only to come around when people were ready for it.
    Take teleportation for example. Humanity knew the theories to transport matter over a distance well before the technology became a reality. Scientists lacked the computing power and bandwidth to turn the technology into a reality. It wasn't until nanomachines could network massive amounts of quantum computing power with nearly unlimited bandwidth that Scotty could finally beam Kirk up long after James Doohan's ashes were blasted into space. Theories existed long before technology. Science fiction writers would dream of the possibilities before the actualization requirements were invented. For example, the theories of time travel existed, but the practice of time travel required so many other innovative ideas to exist.
    After the barrier of time had been cracked, the only barrier left was parallel universes. Humanity knew they existed because people had the option of rewriting their personal history, but according to my younger self, no one had ever found a way to travel between them without making some permanent change. If they bought their younger self a winning lottery ticket, the only way to get back was to intercept the lottery ticket. People rarely were able to change the big events of history, and if they did, all people in the future could do is take their word for it. My younger self said one of the “lost” claimed to kill a dictator in World War II Germany. The “lost” said that Hitler took the dictator's place, and history ended up being worse.
    Thus our only evidence of time travel paradoxes existing was the word of people who claimed to come from another timeline. They might be able to bring a history book back with them, but history books could be faked, especially if it's the only copy in existence. However, a person from the future wouldn't know their history had been altered. To people living in the future, the past was static. The only way to observe a change would be to go back, make the change, and then travel forward again. Schrodinger had explained the parallel universe and alternate reality question during other pursuits. He said that a cat in a box with a vial of poison that may open at any time could be both alive and dead. It wasn't until the box was opened that the state of the cat could be revealed. As soon as people observed the past or opened a history book, they would now define the state of the universe, but until then it was probabilities. So if I killed my grandparents before my parent's birth, rather than the probability of me never existing, there is definite proof that I didn't exist. In a sense, my trip to the past to kill my grandparents was opening the box.
    The only problem is that timelines are a one-way ticket. If my grandparents die because of my decision, I can never go back and bring them back to life. I theoretically could travel back to warn my grandparents about their impending doom. But the more times I cross my own timeline, the greater the chance that I will cause even more problems. So if I tackled myself and beat myself into submission, my grandparents may see the destiny of their grandchildren and never have kids. Or they may have kids but at the wrong time. There was no way to tell how the meddling will affect the timeline until they were observed. And the more times a person traveled back, the more tangled the timeline would become. Trying to fix time is like attempting to untie a knot where you only see part of the rope and have probable configurations for the rest of it. Generally speaking, the “lost” are restricted from time travel because they will drive themselves insane by tangling their timeline or get themselves killed while trying to fix their timeline. Fixing time is like swimming against the gravity of a black hole. Eventually, the person is crushed and wiped from existence.
    My younger self was wise to restrict our conversation. The more we conversed, the