Time travel paradoxes

[alexd]

Now Continuum is over, I am watching those Primeval shows, mostly for the blonde S Club 7 singer who plays a part in it, and because there is noting much else to watch that I haven't seen already, but also because it is about time travel.
I watched the Canadian version, Primeval New World, which only lasted 1 season, and it actually become OK at the very last episode, then it was cancelled. They should have seen that coming.

For me, it was not about the dinosaurs but rather about the time travelling. There needs to be more TV shows about time travelling.

Time travel questions and paradoxes are interesting and I often wonder, if time travel were possible:

1. If you change something in the past, would the future be changed because of it?
2. If you changed something in the past would it start another timeline going forward, leaving the original timeline intact?
3. If you went back into the past would the original you still continue the timeline in the present? And if you met yourself when you came back would you cancel each other out?
4. If time is on a continuum or a line like the TV cliches suggest, wouldn't changing something in the future cascade changes backward to alter everything in the past?

 

[Ho||yw0oD]

Time travel questions and paradoxes are interesting and I often wonder, if time travel were possible:

1. If you change something in the past, would the future be changed because of it?
2. If you changed something in the past would it start another timeline going forward, leaving the original timeline intact?
3. If you went back into the past would the original you still continue the timeline in the present? And if you met yourself when you came back would you cancel each other out?
4. If time is on a continuum or a line like the TV cliches suggest, wouldn't changing something in the future cascade changes backward to alter everything in the past?

My expertise goes about as far as reading a couple Stephen Hawking books and the occasional physics article. My thoughts are that:

1. There are an infinite number of potential realities ("dimensions"?) so for that dimension the future would maybe be altered, but that dimension's future was likely to be different than ours anyway? For the rest of us who didn't do any time travelling our past, present and future would remain the same.

2. Yes, you would have two simultaneous realities as there are already (at least in theory) an infinite number of simultaneous realities.

3. Going back in the past to see myself would impact me in that life, but would have not alter the past when I go back to my dimension. Begs the question on whether or not travelling from the past to the future ("our present") would be possible.

4. Good question and makes me wonder how travelling to the future is possible. It would have to be if safely travelling from past to present is possible. I don't like the thought of this as I don't believe in destiny/fate. I guess you could travel to one possible future but there would have to be an infinite number of possible futures and how would we know, assuming destiny does not exist, which future was the one that would play out?

 

[Jeffsus]

If you change something in the past, would the future be changed because of it?

Short answer, there is no changing of the past. Therefore, there is no changing of the future. This is deemed causality. For example, were you to go to the past, it would already be the past, and resulting future.

if you changed something in the past would it start another timeline going forward, leaving the original timeline intact?

There is only one timeline, the one we live in. Timelines do not start or stop willy nilly depending on Hollywood movies. (black holes possibly excluded)

If you went back into the past would the original you still continue the timeline in the present? And if you met yourself when you came back would you cancel each other out?

Causality dictates that it is impossible to go to the past. Even if, say, wormholes, are possible, still they do not allow travel to the past. Travel to the future on the other hand, is not only possible, but already accomplished by humans.

If time is on a continuum or a line like the TV cliches suggest, wouldn't changing something in the future cascade changes backward to alter everything in the past?

Changing something in the future? This question makes no sense.

-jM
A&D

 

[JamesM]

Reading up on the Enterprise C should answer all your time travel questions. Including how People from the future who go back in time to set an altered future timeline, can also co-exist in the same altered timeline, where originally they didn't exist. Unknown to the persons in that same timeline.

easy.
http://en.memory-alpha.org/wiki/USS_Enterprise_(NCC-1701-C)

 

[NemIsis]

Hope you're joking, James.

Stephen Hawking - The Mad Scientist Paradox - YouTube

Interesting topic. While the multiverse theory could prevent the 'grandfather paradox', it makes more sense that the universe is simpler and doesn't like chaos, therefore causality comes into play.

I also didn't get that last question: cascade basckards?

 

[NemIsis]

Sorry, the multiverse hypothesis (not a theory).

and 'backwards'. lol. God.

 

[JamesM]

well I do know if you meet yourself in the past it will create a time paradox, which will create a chain reaction which will unravel the very fabric of the space time continuum and destroy the entire universe!

worst case scenario.

 

[randyval]

unless we exist in some kind of probability cloud, where everything is happening all at once, which transcends space and time.

 

[lobo]

"If you change something in the past, would the future be changed because of it?"

I kind of like the theory that there are certain events in history that are not possible to change. That they are fixed points in time and history and must occur no matter what. For example, going back in time to try and kill Hitler. Hitler must exist for whatever reason so "Time" will somehow stop you from killing him by maybe tripping over something and losing your one chance.

All that being said, I do believe that if you were to change something in the past, it would affect or change the future.

"If you changed something in the past would it start another timeline going forward, leaving the original timeline intact?"

Yes I think it would. An infinite number of timelines are possible. This is why I never bought into the Terminator franchise with their time travel stuff. It's great but them preventing Judgement Day only benefited them in their current timeline. The other timeline didn't just disappear or blink out of existence it still happened and continues to.

"If you went back into the past would the original you still continue the timeline in the present? And if you met yourself when you came back would you cancel each other out?"

I don't think you'd cancel each other out like Timecop. That show/movie had an interesting concept in that only one timeline existed and whatever changes you did in the past it would affect the future.


Not sure about your last question though.

I think another question should be, should we ever allow time travel? Would there be any benefits to it or is it simply to take a peak into another "world". Would it be something that gets banned and only the terrorists have access to it?

Good topic. Let's keep it going.

Lobo

 

[lobo]

unless we exist in some kind of probability cloud, where everything is happening all at once, which transcends space and time.

Like in Lost?

Lobo