Imagine if humans could travel back in time: maybe you could stop Hitler, or even rob banks and steal purses from old ladies. The possibilities are endless. Of course, the concept of time travel is all hypothetical, but thousands of years into the future, someone might be legitimately asking your descendants this question (since you would be dead, after all). We already have possible leads on time travel, and as we gain more knowledge of the process, our grasp over that golden dial to total understanding tightens. At the same time, we need to be wary of the dangers of time travel and understand why we are so obsessed with it in the first place. Only then can we truly be capable of actively messing with time. 

Time travel as a whole might seem like a modern and completely new concept,  but in reality, our ancient brethren had already begun thinking of the concept. For example, in Greek mythology, the titan Kronos is known for being able to wield and manipulate time after castrating his dad, Ouranus (and I thought my family problems were bad). He could pause it, rewind, you name it. Even God in Christianity shows some form of control over time. For example, in the Book of Revelation, God transports a prophet named John to the future to witness the supposed apocalypse. Clearly, time travel is a concept humans have been thinking about since we could walk on two legs; so why haven’t we unlocked the means of time travel yet? Is it all just an impossible fantasy? 

While technologies are changing and advancing everyday, don’t get your hopes up. Even though you are most likely going to be dead before some means of time travel are invented, you should still be worried for the future of the Earth. Many problems may arise from attempting to meet with your great grandma or even with a past version of yourself. One known problem is referred to as the Butterfly Effect: this is the idea that something small can cause a more far-reaching ripple effect. Let’s say you travel to the past, and in your haste to be sneaky and mysterious, you accidentally bump into a tree. So what? Just apologize to the tree, and move on with your life. Let’s say some poor kid happens to be walking near the tree you bumped into, and a dislodged branch falls off and knocks him unconscious. Well, that’s a bit unusual and unlikely to happen, but what if that kid never finished the intended course of that day? He would never meet the woman who would become your grandma, and he would never end up marrying her or allowing you to be born in the future. What if he cured cancer? What if he became the next Mother Teresa? Well now, he can’t do any of that stuff, since he’s unconscious because you bumped into a tree. Thanks a lot. 

Another reality-altering problem we could get ourselves into with time travel is known as a paradox. There are many different forms of paradoxes, but one of the most dangerous is the Grandfather Paradox. Let’s say you go to the past, and kill your grandfather because he turned out to be a serial killer. You come back to the future…now, what happens? Your grandfather is dead, which means he never married someone and had your dad, which means your dad never married someone and had you, which means you never existed. What happens to you when you travel back to the future? Would you simply cease to exist? Or would something beyond human understanding take place? The scary part is that we have no way of knowing what will happen when you try to mess with time; it’s like playing with fire. And hasn’t your dad told you to never play with fire? Oh wait, he doesn’t exist anymore. And you don’t exist either. 

Unluckily (or luckily, if you hate your dad), some degree of time travel is possible as of right now. For example, in quantum-controlled systems, which are tiny worlds that are composed of a single atom, scientists have figured out how to revert a quark, which is a particle that makes up an atom (yes, your biology teacher lied to you! There are particles smaller than an atom!) back to a destination where it was originally. Essentially, scientists have figured out how to move a quark from Point B back to Point A. Currently, the data is still tentative, but as time goes on (no pun intended) and technology improves, scientists will have more control of quarks and will finally be able to manipulate time in these quantum-controlled systems. And it’s only a matter of time (also no pun intended), until we have that same level of control on a bigger scale. It seems kinda scary, I know, but don’t worry! You’ll likely be six feet under when that happens, so sit back, relax, and pray that no one messes with time so your descendants find themselves reading my article on time travel.  

What would you do if you had the powers of time-travel? Close this computer and think. Would you use time-travel for your own gain, like stealing some hapless old ladies’ purse? Or would you do something noble with time travel, like assassinate Hitler? Personally, I would start my own Ponzi Scheme on Wall Street. Anytime someone tried digging up dirt about me, I would just travel back in time and run over their grandma. Boom! They no longer exist.

At the end of the day, time travel is an interesting and fun concept to talk about. Sure, it might be a world-ending invention once its’ fully fleshed-out, but that’s what makes it such a fascinating concept.