Is Time Travel Possible? - Part 1
The basic premise of the TV series Doctor Who is that using a vehicle called a TARDIS (Time And Relative Dimensions In Space) the Doctor and his companions can travel through space and time.
But just how valid is the concept of time travel? Could we one day travel through time like the Doctor?
Time travel has fascinated science fiction writers for decades. Star Trek was full of time travel paradoxes and events, and even Homer Simpson has travelled backwards in time, courtesy of a toaster he fixed.
Entertainment apart, what are the realities of time travel?
For now Doctor Who like time travel remains outside of the realms of possibility, though there are fringe scientists who claim it is possible and can be achieved. The veracity of these claims have never been fully verified.
Scientists have proved time travel, to a degree is possible. Albert Einstein provided the foundation for the possibility of time travel in his Theory of Special Relativity.
Einstein theorised that an object travelling close to the speed of light would experience time slower when compared to someone who remained stationary. Imagine if one person was in a spaceship travelling close to the speed of light.
If you spent ten years in a spaceship travelling at 95% of the speed of light, you would return to Earth to find thirty two years had passed. Effectively, you’ve travelled through time. As of yet, the space shuttle only travels at 17,500 miles per hour.
This theory has been proved using synchronised atomic clocks. One clock has remained on the ground whilst the other has been flown at a high speed. A small difference in the times of the clocks proves that the faster you travel the slower time goes.
The scientific community are in dispute about time travel. Theoretically it is possible, but the practicality of it opens a can of worms that will have your brain turning in somersaults.
This is due to a theory called Occam’s Razor, which states in layman’s terms that you shouldn’t make more assumptions than are needed. Any theory that allows time travel creates huge issues of paradox that must be resolved.
For example, what would happen if you went back in time and killed your grandfather? Would you immediately cease to exist because he wasn’t alive to marry your grandmother and so you could never be born? In which case, how could you have killed your grandmother?
One way around this is to state that every decision and action creates an alternative universe based on the outcome of that decision. As you can imagine – this would create rather a lot of universes.
Stephen Hawking once questioned whether the absence of tourists from the future constituted proof that time travel didn’t exist. However, much like Star Trek’s Prime Directive, time travellers could have a similar rule of non interference to the time periods they visit (unlike Doctor Who!).
However, there have been a few oddities that may be explained by time travel. In the 1990’s an American investor began to place investments on the stock market. A few years later, apparently, he was arrested by the FBI for insider trading. Usually an investor will make money on a few investments, and lose on others. This gentleman had a 100% success rate on his investments. He had successfully picked small companies and invested in them just before their shares rocketed skyward. On his arrest he claimed vehemently that he was a visitor from the future and had travelled back in time.
Though of course, if time travel isn’t possible, then this opens a completely different can of worms. Why? What laws of physics prevent time travel from happening?
