Let me start off by stating, I do not count myself as an expert in the field of ‘Time Travel’. It’s just something that sometimes keeps me awake at night when I try to get my head around the paradoxes it presents.
So what follows in an introduction to Time Travel and some paradoxes coupled with one of my other pleasures, the Movies.
Let’s face it if I could time travel I would be seriously rich. I would hop into my time machine and see what next week’s lotto results are going to be, easy! Well I don’t have a time machine…yet, but…
Time travel does exist
There is scientific proof. Put simply, we know that as an object accelerates and increases its speed, time relative to that object slows down.
The fastest we could hope to travel is somewhere close to the cosmic speed limit (the speed of light) which is 186,000 miles per second. When our speed is close to the speed of light when compared to the objects around us, then time passes slower for us.
Here’s an example.
Let’s say we begin a journey in the year 2020, and we travel very close to the speed of light. We travel for 5 years at this speed. Now for us only 5 years have passed but when we return to our starting point we find that for the people we left behind 50 years have passed.
We have arrived back at the year 2070 but for us the year is only 2025. We have now effectively travelled into the future.
Here’s another example.
Imagine we build a space ship powered by a fuel yet to be invented. Once the space ship is travelling at 99.9% of the speed of light the following occurs:
For the people on board one day becomes equal to one Earth year.
So we can agree that the theory of travelling forward in time looks good.
What about travelling backwards in time?
You see, all this time travel stuff has to do with Einstein’s theory of general and special relativity.
As we saw above, you might well think of time as a constant, however Einstein showed that time is an illusion; it is relative and can vary for different observers depending on your speed through space.
Going forward in time on a small scale happens already. Satellites with super accurate timing on board have shown that the effects of gravity and increased speed in space (compared with people on the ground) results in a difference of 38 microseconds a day.
If you were in that satellite for 10 days you would arrive back on earth 380 microseconds younger than the people who remained there.
The problem with going back in time is that Einstein’s calculations show you would need to travel faster than the speed of light which causes a big problem.
An object at the speed of light would have both infinite mass and a length of 0. This would seem to be physically impossible however there are some scientists that have played about with Einstein’s equations and think it may be possible.
Worm holes might solve the problem; we could create them to connect points in space time. They are still mostly hypothetical, they haven’t been observed even, plus we are nowhere close to knowing how to create one in reality.
And then there is the problem of how to overcome the Time Travel Paradoxes!
Three Time Travel Paradoxes
Great minds past and present agree that whilst travelling forward in time is possible travelling backwards is not. Time travel paradoxes would prevent us from doing this.
Imagine going back in time and preventing your parents from ever meeting each other. You would not be born; you wouldn’t exist, so how could you have travelled back in time in the first place.
Here is a brief explanation of 3 time travel paradoxes:
1. Predestination Paradox
This paradox means that things are always destined to turn out the same way, and that whatever has happened must happen.
Let’s say your pet dog got run over last year. You travel back in time to prevent it from happening. On the way to save your dog you mistakenly run her over.
No matter what you do you will only ever create that event which you are trying to change. In other words, you going back in time is what then causes the event to happen that you are trying to stop, rinse and repeat.
2. Bootstrap Paradox
This paradox is when any object, person or information sent back in time exists without it ever being created. So imagine J.K Rowling going back in time to give her younger self the complete Harry Potter manuscripts. She gets them published and becomes famous, at which point she then travels back in time to give her younger self the manuscripts.
You see, the manuscripts have no point of origin.
3. Grandfather Paradox
This is a cool paradox, mainly because it’s easy to understand. Imagine my Grandfather is an evil genius hell bent on destroying the planet.
So I travel back in time to kill him before he becomes the evil genius he is today. Do you see the problem? If he never existed then neither would I so I couldn’t go back and kill him.
I know what you are thinking, what would happen had I travelled back and pulled that trigger? It’s believed that a predestination paradox would occur (see above) or else I would successfully kill him but on my return to the present all traces of me have been erased. Yet I am here in the present, therefore I have created an alternate or parallel universe.
The other amazing thing about this paradox is this: If my Grandfather didn’t exist then why would I even want to travel back in time to kill him in the first place.
Three Time Travel Movies I Recommend To My Friends
Time travel is a great topic and it’s no wonder that the movie makers have made so many films on the subject.
You might not know this but in addition to anything science related I also love TV and Movies. So I thought it would be cool to list some Time Travel movies that I love.
Warning: these are three films that whilst I would , and indeed have recommended them to my friends they are not full of special effects and loads of green screen stuff. In fact two of the three are very low budget movies.
I just really like these films and I think they are considerably underrated.
Give them a go, especially if your are a bit of a Sci-Fi nerd like me
Time Lapse (2014)
Three friends discover a mysterious machine that takes pictures 24hrs into the future and conspire to use it for personal gain, until disturbing and dangerous images begin to develop.
It’s a much underrated film in my opinion and I really don’t know why. Actually it is probably due to its low budget and lack of special effects.
It’s very cool, well-acted and has a great script. It’s quite different from other films of that genre.
Primer (2004)
Four friends/fledgling entrepreneurs, knowing that there's something bigger and more innovative than the different error-checking devices they've built, wrestle over their new invention.
Hmmm, ok I’m not going to lie, I don’t know if you will like this or not. Its not the easiest ride, but definitely worth seeing through to the end. You may (will) at times wonder what’s going on. The budget must have been tiny and to be honest the acting at times isn’t great.
Having said that, it is still a film I would recommend to my friends, it’s hard to say why. Just watch it and see what you think.
Predestination (2014)
For his final assignment, a top temporal agent must pursue the one criminal that has eluded him throughout time. The chase turns into a unique, surprising and mind-bending exploration of love, fate, identity and time travel taboos.
This film is excellent, it’s just very entertaining and damn clever.
Photo Credit:
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