Will Time Travel be possible?

[PK]

I do kinda like/ dislike the parallel worlds thing.

It means somewhere I'm a world famous movie star that can fly and strangles raptors with my bare hands for fun.

I dislike it because thinking like that makes me think "Damn, I really got stuck in the bad parallel earth."

Also, I think this theory's possible, just incredibly mind-numbing.

Also, in some universe, I died typing this. In some universe, you died reading it. :D

 

[EvilCrazyMonkey]

So we've moved on from time travel to destiny?

yeah sorry you're going to need to back that up a hell of a lot more than you've done

Destiny implies predetermination. I'm saying that only one sequence of events will happen, and that many things influence it.

 

[CNiall]

Destiny implies predetermination. I'm saying that only one sequence of events will happen, and that many things influence it.

If only one sequence of events will happen no matter what you do, isn't that essentially destiny? Back it up.

 

[1. Luftballon]

Destiny implies predetermination. I'm saying that only one sequence of events will happen, and that many things influence it.

If it were predetermined, then it would not be influenced by anything that did not happen before the determination.

 

[Eevee]

Destiny implies predetermination. I'm saying that only one sequence of events will happen, and that many things influence it.

preposterous

events on the quantum level are purely random; predetermination is impossible

 

[Jetx]

Time Travel in itself brings along something of a paradox. I don't see it ever happening.

 

[Autumn]

I would love to believe that time travel would one day be possible; however, with today's technology it seems fairly unlikely. I've toyed with the idea that time may be a concept and everything that happens is just something that happens, not something that happens over time, and it's entirely true that you can't prove the existence of time (as far as I know).

But then again, I don't know all that much about physics.

I'm not entirely convinced by the arguments that "if people traveled into the past it would make the present so different from what it is now etc. etc.". Because if, for example, somebody from the year 3080 went back to the year 1500 and changed something in the past, well... even though the person was from the future, his actions in the past have /already happened/ in 2008. Therefore his actions in 1500 have contributed to the present we know; in fact, if he /hadn't/ changed whatever it was he changed in 1500 then the present might be completely different for us now.

So, assuming that time travel is indeed possible, every event in the past that time travelers will ever alter (before this moment in time) has already happened. Although I suppose that /does/ say something about destiny, eh?

Anyway, if my theory is correct then this would mean that going back in time to alter the present is actually impossible. Again with what somebody mentioned before by replacing the baby of Hitler's mother with another baby -- the replacement baby would have to be the actual Hitler that we all know of. Therefore, it would have been destined on April 20, 1889 that you would travel back in time in 2008 and switch the babies.

^ This. I've been looking at time travel for a while now and forming theories and ideas on which time travel would happen should the travel ever be possible (the two ideas are the BttF plot aka if you change something while in the past you can see the difference when arriving at your own time and b. the above quote). This is explained pretty well; let's say someone had gone back in time to, I dunno, 1400 and, say, killed someone who would later become ruler of the world. Now, before 1400 this person was going to become world ruler and it would have an effect on today (say that it was to be a monarchy system and we have a world ruler today). Today we would be living under a world ruler and monarchy, had the time-traveller not come back to 1400 and killed the future-ruler. We have no memory of such a ruler, it's not mentioned in textbooks, etc because there never was this world ruler. Unlike in BttF and similar concepts, the world was not once under a world ruler and then, when the time-traveller killed the world ruler, it suddenly "warped" to our current world and that's what we remembered instead of the world ruler (not that that could happen anyway, since 1400 isn't moving parallel to 2008 --1400 already happened). It's entirely possible that a time-traveller went to 1400 and stopped such a thing. We would have no clue.

That's my thoughts on the subject.

 

[opaltiger]

Back to the Future I and II are consistent; it's just not explained well on-screen (for the sake of suspense most likely). 2015 changes around Doc, Marty, and Jennifer a little before Biff returns from 1955; they are just not in any position to notice.

Dammit, I was fairly sure there was a bit in II in which Doc explains something about alternate timelines. :(

However Prisoner of Azkaban, albeit not nearly as awesome, works too.

 

[Autumn]

Dammit, I was fairly sure there was a bit in II in which Doc explains something about alternate timelines. :(

There was. I haven't seen the movie in a while, but there was one part where I think they were in 2015? *unsure* and Doc says that because Biff did something in 1955 (right? *still unsure*) then, after 1955, there was a tangent timeline that they were now following. Marty suggests they go back to '85 and fix it, but Doc says they would be in the tangent there too, and the only way to fix it would be to go back to '55.

Prisoner of Azkaban makes my head hurt :[

 

[Drifloon Rocks]

The main reason that I don't think time travel would be possible is the grandfather paradox. Go back in time and kill your grandfather. You were never born, therefore you never went back in time to kill your grandfather. It never ends.

 

[Twilight Dragon]

As cool as time travel would be, it would cause loads of paradoxes, and eventually the entire universe would collapse upon itself.

Not to mention that time is an extremely.. abstract thing, and it would be very, very hard to figure out how to manipulate it to the point where we could go through without dying.

 

[Eevee]

Dammit, I was fairly sure there was a bit in II in which Doc explains something about alternate timelines. :(

There is. How is that any different from what happened in the first movie? Marty created an alternate 1955 in which his parents are cool. I don't think II was necessarily trying to imply that there are actually two timelines existing simultaneously and that people in the other one were wondering what happened to Marty.

That wouldn't really make sense, anyway, as there's no obvious line to draw to differentiate these cases. If I go back in time and change something to make the world dominated by a race of mole-men, sure, under alternate-timeline rules this would be a different timeline. But if I go back in time, chill for an hour, and then come back.. well, nothing is significantly different, but I still changed events and thus I should still be in an "alternate" timeline, so I will appear to simply never return to my native timeline.

However Prisoner of Azkaban, albeit not nearly as awesome, works too.

Predestination rules make for cool storytelling -- once -- but from a practical point of view are almost entirely useless. :( I do, though, recall thinking that some of the risks Hermione mentioned don't make any sense in the context of time travel that only allows for performing actions which already took place.

The main reason that I don't think time travel would be possible is the grandfather paradox. Go back in time and kill your grandfather. You were never born, therefore you never went back in time to kill your grandfather. It never ends.

There is no "it". Time is not a conscious being that attempts to keep cause and effect sensible. Pretty much any model of time travel you care to name has resolved this problem.

 

[Evolutionary]

If you just randomly think about it well it seems cool because you think "I can go back in time and say the answer to the maths question now that I know the answer" but others could do that to and our world would be really messed up. It wouldn't actually be that great. If you think about it, it really would kinda suck.

From EeveeSkitty

 

[Cryssie]

If you just randomly think about it well it seems cool because you think "I can go back in time and say the answer to the maths question now that I know the answer" but others could do that to and our world would be really messed up. It wouldn't actually be that great. If you think about it, it really would kinda suck.

From EeveeSkitty

Er... you think time travel would suck because people would use it to cheat at tests?

 

[Valerunner]

Police boxes.



I've thought about and believed this idea for a very long time.

But what about the choices of other people? It can't possibly be that every choice you make leads everyone else to go into the very same alternate world, otherwise theirs would have to do the same to you. That...Doesn't seem credible.

Then it means that we have an infinite amount of parallel universes popping up everywhere. Which would make time travel(if it ever became theoretically possible) highly dangerous and even one stray machine that tries to pierce through its timeline will cause all the universes to deflate and implode.

 

[Eevee]

If you just randomly think about it well it seems cool because you think "I can go back in time and say the answer to the maths question now that I know the answer" but others could do that to and our world would be really messed up. It wouldn't actually be that great. If you think about it, it really would kinda suck.

why do you even post

from Eevee

Then it means that we have an infinite amount of parallel universes popping up everywhere.

the many-worlds interpretation says this is already happening every time a being with free will makes a decision

Which would make time travel(if it ever became theoretically possible) highly dangerous and even one stray machine that tries to pierce through its timeline will cause all the universes to deflate and implode.

what

why would this happen

universes are not balloons

 

[Time Psyduck]

As I recall there's a theory that the Large Hallidron Collider (or maybe something else similar) could end up being a time machine and people could come from the future.

I'm not convinced about time travel, but I recon if humanity carries on as it has been doing there's a good chance we/our childern/thier childern may find out how to do it.