If you could go back in time...

[PNWDweller]

If we could go back in time though, would we be able to travel forward assuming we could go backward?  And would we want to go forward or live it out the way it would change our life?   And if we could go back in time, would we have the same knowlege as we have now about the future (our past but future for then?)  And if we could go back in time, change the little things, or make money with lottery, sports alamanac etc...would you want to give yourself the info like they did in Back to the Future II and leave to reap the benefits, or would that be impossible as you could virtually morph into something that you wouldn't have been before?

 

With that though, if I were to be able to go back into time:

 

I would go back to 2005, a couple of years before my Dad passed and try to spend as much time with him as I could instead of taking it for granted.

 

Not sure why that particular year, but it was then, that his health started going down and I wish I could have been there more for him. 

[thomastmc]

If we could go back in time though, would we be able to travel forward assuming we could go backward?  And would we want to go forward or live it out the way it would change our life?   And if we could go back in time, would we have the same knowlege as we have now about the future (our past but future for then?)  And if we could go back in time, change the little things, or make money with lottery, sports alamanac etc...would you want to give yourself the info like they did in Back to the Future II and leave to reap the benefits, or would that be impossible as you could virtually morph into something that you wouldn't have been before?

 

Travelling forward in time is already possible. The flow of time is not constant, and is changeable based on a few different factors, such as gravity and acceleration. So, you could merely slow the rate at which time passes for you. You might think you've spent 1 week in the machine, but hundreds of years may have passed on the outside. While this has been done in the lab, and observed on satellites, it has not been done anywhere near to the degree of the example I used of 1 week for hundreds of years. Still, the only thing stopping one from reaching the outcome of the example is the energy expenditure required. If you could travel at more than half the speed of light, which is perfectly possible, you could easily travel forward in time.

 

From the commonly held perspective of theoretical physics, if you could go backwards in time you'd likely be creating a new parallel timeline.

 

For instance, if you went back in time and prevented something, or gave yourself information of the future, the timeline you originated from would not change at all (except that you'd no longer exist there from the time when you'd left). You'd be creating a new timeline that exists in parallel with the one you left, and your changes would only be of consequence to that new timeline.

 

Take the old paradox; If you went back in time and prevented your grandparents from giving birth to your parents, what would happen to you? The answer is believed to be, essentially nothing. You would still be born in your original timeline and you would still exist in the new timeline. The truth is, the people you interacted with wouldn't even really be your true grandparents, but rather copies of them, basically no different than exact clones.

 

When you return to your original timeline nothing has changed, but you probably can't return to your original timeline. You'd probably either create a new timeline or simply travel ahead in the timeline you've already created. The outcomes of that new timeline will very probably be different than those of your original timeline, so when you got back to the year your journey started things could be drastically different than they were at the same time in your original timeline.

 

As they say, a butterfly flapping it's wings in South America can change the weather six months later in China. The chances of every single event in your new timeline going the exact same way as in the original, or even happening at all, are virtually nil. Like shaking a snow globe, you'd be shaking up the foundations (or "snow") of reality (like tossing a cup of 1 trillion dice). Even though the conditions are basically the same in the snow globe every time it's shaken, the resulting paths (or patterns) of the "snow" inside is never exactly the same. Basically, all it takes is a stray electron for an event to have a different outcome. Suppose a spark produces a fire in a rocket causing an explosion and the Apollo program is dismantled, or Hitler decides to become an artist instead of a dictator bent on world domination. The things that seem as if they were inevitable in our timeline, and therefore in another timeline, are merely the unpredictable whims of quantum particles, such as the electrons in our brains.