It’s time for some bad news. No matter how fast your DeLorean can go, or how much you spent on that life-size Tardis model, there is absolutely no way go pick up Socrates and Napoleon for your history final. It’s a tough pill to swallow, but unless the human race manages to expand beyond the confines of the fourth dimension, travelling back in time will forever be isolated to fiction. But don’t leave quite yet, we haven’t ruled out our part in the future.
It’s as plain and simple as it is shocking. Time travel is COMPLETELY possible and there are multiple ways to go about it. None of them, thankfully, will leave you in a universe-shattering confrontation with your future self that will tear apart the fabric of space and time. The first of which is a tricky thing called time dilation.
The theory of relativity identifies time dilation as a difference in elapsed time relative to velocity. A physical example is if two people synchronized extremely accurate watches and one of them flew around the world in a jet while the other stood still, the one that had been on the plane would have fallen behind the other. This phenomenon is attributed to the magic of perspective. In its simplest terms, the watch speeding through the air observed more distance traveled in the same amount of time than the watch on the ground. To most, it makes no sense, but the general consensus is that time dilation is completely insignificant… for now.
The Apollo 10 mission hit a top speed of almost 25,000 miles per hour, setting the record for the fastest a human has ever traveled. Yet even at such extreme speeds, time dilation displays little to no visible effect. This is where the “yet” comes into play. Hypothetically, if a human being were able to travel at 99.99% of the speed of light for 10 years continuously, when he or she returned to Earth, nearly 7,000 years would have passed. Granted, with modern technology, it currently takes a 17 mile long, nine billion dollar Hadron Collider to accelerate merely a subatomic particle to anywhere near this speed. But no one knows knows where and when we will end up as we continue to push the boundaries of science.
Depicted in the groundbreaking sci-fi film “Interstellar,” a much more tangible form of time travel can also be explained through Einstein’s Theory of Relativity. While Astronaut Joe Cooper, played by Mathew McConaughey, travels dangerously close to a black hole, mere hours on a desolate planet equate to over 20 years back in orbit. This is known as Gravitational Time Dilation.
Relativity states that the greater the gravitational force on an object, the slower time will move respectively. This means that if you died at age 100 on earth, you would live just a few minutes longer had you been on Jupiter.
The possibilities for time travel are endless, seeing that so is time. It may not be quite as glamorous as stepping into a Tardis or taking the DeLorean up to 88 miles an hour to weave in and out of the fourth dimension, but we should stick around anyway. As the quote was mistakenly attributed to Einstein, “Time is what keeps everything from happening at once.”