I’d really like to write a story involving time travel, but whenever I contemplate it, it completely messes with my mind. Nonetheless, I have gone into the twisted labyrinth, and pondered the possibilities on many occasions.

One of the twistiest questions is: If you go into the past, can you change something? Or was it always the case that you went into the past, and therefore your actions were already part of the time continuum? This taps into the argument of free will and personal choice versus destiny. I guess at some point we all wonder: Do we have control over the future?

I have great admiration for the authors who have tackled time travel tales and produced some outstanding stories. There are many from which to choose.

The most thought-provoking are those that allow protagonists to change things in their past, but not without consequences. Sometimes, as in The Butterfly Effect we see repeated attempts to change events, which lead to more and more complicated consequences, and the protagonist’s desperate attempts to put right what he caused to go wrong, culminating in a desolate sacrifice. I think the story warns that even if we had the power to change the past, we ought to leave well enough alone. We are meant to make mistakes and learn from them.

In Star Trek, there are many time travel episodes. My favourite was Star Trek, Deep Space Nine, Trials and Tribble-ations. I loved it because the creators of the show used footage from the Star Trek Original Series episode The Trouble With Tribbles. The story they created, and the way they interwove the new footage with the old was seamless and very entertaining. In Star Trek, they’ve interfered with time so often that a Department of Temporal Investigation sends out agents to make sure timelines are preserved.

I understand the need to preserve timelines. Even small changes could ripple into large effects. Some of the more entertaining and humorous tales involve characters trapped in loops, where periods of time repeat again and again. It allows protagonists to experiment, and a chance to replay, if things don’t work out well. In Groundhog Day, time looped for protagonist Phil Connors until he learned to be a better character. When he came to consider someone else’s happiness before his own, he finally found happiness himself. It would be nice to think we could have endless chances to make better choices in our lives. But perhaps we do, if we think of each new day as a fresh beginning.

In Star Gate SG1, Window of Opportunity, Jack O’Neill and Teal’C make the most of their time loop, doing things they wouldn’t consider doing in their normal lives, free in the knowledge that the next repeat time loop would wipe those actions from existence. It’s an attractive notion, and a fun fantasy, to have the freedom to act without permanent consequences catching up with you.

The direst consequence of time travel into the past, is accidentally doing something which results in wiping yourself out of existence. We see this scenario in Back to the Future, where the main character, Marty, accidentally prevents his parents from falling in love, and he must work to resolve a complicated series of events and bring them back together, with the desperate high stakes of time ticking down, before he and his siblings disappear.

The series of three movies, directed by Robert Zemekis, are full of all the things we expect from good movies: excellent characters, action, adventure and comedy. I love them for all those reasons, but I also love to see how time travel-tackling authors imagine the future to be. Back to the Future had some fun elements: hovering skateboards, holographic sharks swallowing people from a movie theatre billboard, instant hydrating pizza and self-fitting clothing.

Time travel can also be achieved through the effects of time dilation. Astronauts experience space-time relativity as they cross space at velocities approaching light-speed. The faster they go, the more time slows down for them, relative to those they left behind on Earth. Anyone who goes on such a space journey and returns to Earth, will find themselves in the distant future.

The time dilation effect can also be caused by the extreme gravitational forces of a black hole. The closer a traveller gets to the event horizon, the more time slows down for them. This is what happened to Matthew McConaughey’s character, Joseph Cooper, in Interstellar. He remained a young man while on his journey, which skirted close to a black hole, but by the time he returned to Earth, the daughter he had left behind was an old woman.

Yet another theory proposes that time branches with every choice a person makes. Each new branch is a separate timeline, continuing on for every possible alternative. Given that our lives are interconnected, and that our choices affect not only ourselves, but other people too, the network of possible choices and timelines is mind-boggling. I imagine that if a person could transport to an alternative timeline, it would be an almost impossible feat to find and return to the original.

I often wonder what my life would be like now, if I’d made different choices. I feel certain that I would be in a different place and probably be a different person. Similar perhaps, but not the same. If we knew the outcome, would we change our past? As in the time dilation scenario, there would be sacrifices. I’m not sure I would go back. I value the lessons my past has taught me.

I wonder how many people consciously consider the consequences of the choices they make each day. Perhaps that’s the real value of pondering time travel. At present, time travel is not possible, and most likely, never will be. We have to consider our future now, in the choices that we make.

The movie About Time, considers this question. In the end, the message of this movie is that we should be more mindful, and appreciative of our present.

I’m glad we have so many stories of time travel, prompting us to think about these things. Perhaps one day I’ll tackle a time travel story of my own. Who knows? We’ll find out in the future.