Let’s pretend for a moment that I did have a time machine.
I have a multitude of choices infront of me.
Let’s explore a few scenarios in a moment. Firstly, what would be the motivation for time travelling? They probably fall under one of these 3:
- To change something that happened
- Curiosity 1 – to see what happened in the past for yourself
- Curiosity 2 – to see the future.
The major problem with the first, is that if you do successfully change something, you create a new branch in the timeline and cut yourself off from your old one. Travelling forward a week will not get you back to your point of origin, merely one week into the future of the new time line. Dangerous if you were to do something like accidently run down your grandfather before he impregnated your grandmother…
The other two are pretty harmless I spose…
Now lets unwrap a few scenarios.
Scenario 1: Travel back one week.
Now, do you:
- A: choose to either interact with your one week younger self, or
- B: not?
1A: What if I choose to instruct my one week younger self not to time travel next week? Would I suddenly blink out of existence? Or would there be 2 me’s running around from that point on? Could be handy for mischief!
1B: If I don’t meet my younger self, in a weeks time he will travel a week back in time to become me. No harm done. The only affect would be that next birthday I will actually be 1 year and 1 week older.
Scenario 2: Save someones life in the past
And then leap back to the present. As we saw in the movie The Butterfly Effect, you never can tell what effect that would have. God might just want that person dead.
Scenario 3: Travel back a week and buy a lottery ticket with last nights winning numbers
Sounds good! You could even mail the ticket to yourself if there were some sort of restrictions on carrying objects through time (The Terminator was naked so you probably will be too)
Scenario 4: Travel forward one week.
If you were to reak some carnage while you’re in the future and then travel back in time to when you left, your timeline will remain unchanged because the carnage was caused by you but you came back so the carnage doesn’t stick from your perspective. It comes back to that line you often hear in movies “the future isn’t set”. If you stayed in the future then you would be subject to the consequences of the carnage.
Summary so far
It is very dangerous to travel to the past because changes you make break the connection with your place in the present. If you travel to the future do what you like as long as you come back.
One more problem
I think time travel technology has one major limitation to overcome. If you were to travel back in time exactly one week, you would appear in the same spot in the universe seven days earlier. Unfortunately, because the earth is travelling at thousands of kilometres a second as it swings around the Sun, it won’t be there to pick you up. You’ll be deposited in deep space, and because you’re naked, frozen instantly. The solution to this would be to travel through time and space. You’d have to calculate the exact point in the universe you want to arrive and when. In that case you could travel anywhere in the galaxy! But really, you are kind of limited to earth, because you don’t want to turn up naked on Alpha Centauri!