Time Travel and why it can't work...

[unluckyseventeen]

Here's a conundrum for you...

I've had the most epic argument about a FAKE situation regarding time travel before, and I was randomly reminded of it today. Here's the situation:

Say there's a guy that has a time machine. He goes to the store, buys the gun, and goes home to his time machine. He takes the gun in the time machine and travels back to 5 minutes ago, while he was buying the gun. He goes to the store, finds himself of 5 minutes ago, and fires the gun at his former self's head. What happens?

My theory is that they both cease to exist once the former self is killed by the future self. The bullet would travel into the head of the former self, and that same wound would HAVE to exist in the future self's head. So, they would both simultateously fall to the ground with the same identical wound.

Or would they?

Another theory I had is that once the bullet was fired, it would kill the former self, and the future self would simply dissapear, because that in itself would prevent the future self from even existing... only for the simple fact that because the former self cannot travel back into time to achieve this task. However, the issue here is: when would the future self dissapear? When the former self was supposed to travel back in time, or at the time that the former self is killed?

Or...

The causation of killing one's former self would not be allowed to happen by rule of the space-time continuum, because if that happened, the time traveler would cease to exist because the time travel therefore cannot take place if his actions are interrupted. However, this is not caused by death, it can be caused by anything. Say this incident happens but the time traveler disappears, and the action of the former self is interrupted by a few seconds, making him late and missing his time travel that is schedule in the near future. Then again, if that happened, the time traveller would never even be able to do so because he would have to know that his actions would interrupt his own existance.

BUT, what happens to the guy when he's supposed to travel time? In the first time around, there is no meeting. The guy buys the gun, and goes home. In the second time around, the guy is halted from ever travelling time. Therefore, because of this there would be a second reality created, and every person would be duplicated into two realities, except the time traveller because he ceases to exist in the second reality.

What the...

So, if there's a second reality, and time travel is the only way to access it... WHERE exactly does it exist? It has to be a place, unless the entire world is just an idea. And by travelling time this idea is therefore disproving the existance of the entire world. Every person, and every instance that has ever happened and will happen is interrupted and the world must end. Right?

Ugh...


If you think about this enough, your brain will go crazy, as mine is now.

Anyway, me and my brother argued about this for DAYS on end. What's your theory?

[unluckyseventeen]

I guess nobody cares...

[Future_herp.]

That is amazing. I have been thinking about it all day so far.

The causation of killing one's former self would not be allowed to happen by rule of the space-time continuum, because if that happened, the time traveler would cease to exist because the time travel therefore cannot take place if his actions are interrupted. However, this is not caused by death, it can be caused by anything. Say this incident happens but the time traveler disappears, and the action of the former self is interrupted by a few seconds, making him late and missing his time travel that is schedule in the near future. Then again, if that happened, the time traveller would never even be able to do so because he would have to know that his actions would interrupt his own existance.

I agree the most with this one

[Torin]

Well, theoretically, you wouldn't be able to travel through time as you would be violating the law of conservation of matter and energy. Travel back in time 10 minutes and you have the sudden creation of matter in the past and the destruction of matter in the future.

I suppose you could have an equal amout of matter transpose with you, but that would be tricky to manage.

Also, there are some good theories about how it might be possible to tow one end of a wormhole through space at relativisit speeds and have the towed in in the future and the stationary end in the present. (The towed end is time-passage locked with the stationary end.) This one might work if you can tow it to a nearby star and then back. You might be able to travel that way as the universe 'sees' the matter through it's whole trip.

Now we just have to find a way to create stable wormholes that don't involve gravitational singularities.

[zsanorah]

ouch my head hurts!

[Lfsabch]

ive thought of my own a long time ago close to yours, but i was dead set on this:

ok try to stay with me on this, ok: so the future you is supposed to go back in time and kill the past you, this i believe would send space and time into some sort of conflict, because if the future you goes back and kills the past you before he has a chance to go in the time maching then that means the Future you could not have time traveled.

now with that it brings up the issue that well if the future you couldnt have gone back then the past you would still be alive,

following?

so in a situation like that, and assuming hteres no other states of reality and such, then it is a conflicting situation that has no end,

because how can you go back in time and kill yourself and still be alive in the future to go back and do it.

i've gone crosseyed

[JuliusSqueezer]

Dude, you don't need a time machine to shoot yourself in the head. You just need to marry poorly and take a lot of crap for a few years.

[Lfsabch]

^touche

[unluckyseventeen]

Hahah, best ending to an explanation ever...

i've gone crosseyed