NationStates Jolt Archive

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?

Too many paradoxes to think about... but there is only one way to really know what would happen.... TIME WARP! :)

time is like any other dimension and can be navagated in multiple directions,
but yes if you happen to pull it off it is going to seriously fuck up the fabric of existence

If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?

That's when your deja vu kicks in.

Time is one-directional. You can speed forward, but you can't go back.

Current theories in physics don't disprove the possibility of time travel. But I think it's one of those "self-fulfilling" things. A closed loop, or something like that. Can't really elaborate, as the books I read about this are very far away.

This has been alluded to in a previous post, but basically, if there are multiple worlds/timelines/dimensions, then the biggest paradox of all - the grandmother paradox - breaks down, as you simply create a new world by killing your grandmother and she remains healthy in your original world.

Some scientists believe there MUST be multiple worlds in order to account for being able to predict where quarks will move. Or something like that. It was something I read a year or two ago.

I was told that some whole wormhole thing could propel you back, but I find the paradoxes disprove it.

I something could go faster than the speed of light, the theory of relativity states that it would be going back in time...don't know much more than that.

Paradoxes only disprove it if you are unwilling to accept the idea of multiple/alternate dimensions. Example; You go back in time and punch yourself in the nose. The you doing this remembers nothing, because he came from a dimension where this never happened; however another you does remember, and a third you might have pre-empted your attempt and broken the future you's nose.

And the fact that paradoxes might result doesn't make it impossible. It just makes it potentially very unwise.

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?



yea, what if you decided to go backin time and stop the time travel dvice from being invented?

Time travel rocks.

Time is one-directional. You can speed forward, but you can't go back.

Time travel going forward is proven (you travel forward in time at the rate of one second/second), and I can easily imagine that there might be some way to speed up the process (eg traveling forward at the rate of half a second/second, double speed) or slow it down (two seconds/second) but with that method the best you could do is 'pause' time. Another problem with backward time travel is that you are going to a place that no longer exists and will not exist in the future.

The only way I can imagine to solve this is that rather than travel backwards in time, you would have to jump from now to then without travelling between them. This isn't clear I know, I'm sorry, but it is the best way I know of describing my concept. It's like if you travel from London to L.A. without time lapsing and without actually travelling because you did not exist between those two points. You just existed in London then L.A. with no in between. I hope I haven't confused myself again... :confused:

You can go back in time, there is nothing logically preventing it. You just would not be able, in this universe, to do something that was not done, because obviously, if you went back and did it, it was done. Some action can not be both done and not done, so you would not be able to do it. (Why not, physically, is another question.)

Time does not exist. Time is only a way to reference the position of your person in comparison to the sun and other stars, via revolutions and rotations......You can call anypoint in "time" 1 b.c. Now for those of you who are going to bring up the age point. All that is is a way to reference what all is biologically happening within your body. More growth than decay. or more decay than growth. Maybe equivalent growth and decay. Bwuahahaha I vin!

Time does not exist. Time is only a way to reference the position of your person in comparison to the sun and other stars, via revolutions and rotations......You can call anypoint in "time" 1 b.c. Now for those of you who are going to bring up the age point. All that is is a way to reference what all is biologically happening within your body. More growth than decay. or more decay than growth. Maybe equivalent growth and decay. Bwuahahaha I vin!
The simpelest answers are always the best ones.

The simpelest answers are always the best ones.

Hehehe thanks.

did I win?

Time is a dimension. It exists. Einstein has shown that the best way to explain gravity is using time as a dimension, and experiments have produced observations supporting his theories.

I think I'll worry about time travel when it happens.

easiest way to explain it. Why can't it just work? hehe well I don't have "time" to argue this one out. goodnight.

Time does not exist. Time is only a way to reference the position of your person in comparison to the sun and other stars, via revolutions and rotations......You can call anypoint in "time" 1 b.c. Now for those of you who are going to bring up the age point. All that is is a way to reference what all is biologically happening within your body. More growth than decay. or more decay than growth. Maybe equivalent growth and decay. Bwuahahaha I vin!

The simplest answers are often, however, half wrong.
Time is not just a way of describing a point in a continuum. It is also an absolute ordering of things within that continuum. Yes I can define any moment as moment 1. But this does not change the fact that things have occurred before moment 1. and things will occur after moment 1. We have two different types of time. (A series and B series from McTaggert). One is as you describe. Points that are defined. The other is as I have described a proghression along a defined sequence. As your definition does not describe a logical space within which movement would be possible, then no backward time travel would be possible in it. Mine however is an ordered set, so movement any direction within that set is theoretically possible.

No. you don't win. You get half a medal only.

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?

Oh yeah? At the top of this page, it says "Welcome, Crapholistan. You last visited: 01-01-1970 at 1:00AM"
I haven't visited nationstates in 1970 yet, but I must have, since it tell's me that I did. and then I'll have to wait through the 80's and 90's before posting here again.

Time is a dimension. It exists. Einstein has shown that the best way to explain gravity is using time as a dimension, and experiments have produced observations supporting his theories.

On the interesting relationship between time and gravity (gravity is a distorion of space-time by mass) there's an interesting article I found here (http://physicsweb.org/articles/news/5/2/11) while wondering what other dimensions there may be.:)

Oh yeah? At the top of this page, it says "Welcome, Crapholistan. You last visited: 01-01-1970 at 1:00AM"
I haven't visited nationstates in 1970 yet, but I must have, since it tell's me that I did. and then I'll have to wait through the 80's and 90's before posting here again.
five bucks says you crack before you make it out of the eighties

Yes I can define any moment as moment 1. But this does not change the fact that things have occurred before moment 1. and things will occur after moment 1.

What about in the beginning? If time is a manifestation of the universe then before the universe there was no time. Therefore at the very start wouldn't T=0 ? If there was no time before zero then there wouldn't be <0 . (Gee, I hope I got this right?)

Ok, personally, I believe (hope) that time travel is possible, but one argument that I've heard against it is that, if time travel is possible, then wouldn't we have met time travelers from the future by now? But then I said, "Well, what if they kept a low profile?" Well, I figured they were bound to mess up now and then, but then I thought of the possibility that maybe they have some kind of memory-wiping device with them, since they're from the future. So basically, this whole post has been me contradicting myself. Woohoo...

five bucks says you crack before you make it out of the eighties

I allready did it once, it wasn't easy. I'm used to Duran-Duran and the spiky mullets now, so I think I can do it again...

I something could go faster than the speed of light, the theory of relativity states that it would be going back in time...don't know much more than that.

To be fair, special relativity predicts an imaginary number for time dilation if your speed exceeds C, not a negative one. Can't really be sure what that means physically, of course. Perhaps you cease to exist or something.

Ok, personally, I believe (hope) that time travel is possible, but one argument that I've heard against it is that, if time travel is possible, then wouldn't we have met time travelers from the future by now? But then I said, "Well, what if they kept a low profile?" Well, I figured they were bound to mess up now and then, but then I thought of the possibility that maybe they have some kind of memory-wiping device with them, since they're from the future. So basically, this whole post has been me contradicting myself. Woohoo...

Or they all went to the 1960's and blended in...:p everyone tripping too much to notice and all...

You can see the past and that is true, well kind of anyway.
If you go into DEEEEEEEEEEEEP space and take with you the most powerfull telescope, you can not even imagine how powerfull, known to man after ca. 3000 years you can see the light from earth, fires etc., many centuries ago. and probably see the people that stand near the lights on the ground. In theory ofcourse. :)

As I said before, it is not theoretically impossible to go back in time. That doesn't mean it's practical. It's theoretically possible that if I run at a brick wall I could pass through it unscathed. I don't think the lack of time travellers proves anything, is the point I was trying to get at. I just like to bring up the running through a wall as often as possible

Some of you may find this interesting. <<----{Click} (http://www.fourmilab.ch/rpkp/)
_______________________

Also, would this be a good place to mention that I am a pre-cognitive?

Or they all went to the 1960's and blended in...:p everyone tripping too much to notice and all...
Hippie: whoa dude, you've like, got a laser gun....
Hippie #2: dude, can I try it out?
time traveler(TT): um. no. *ZAP*
Hippie #1: Dude, you disintigrated him...whoa, i said "disintigrated"...i must be wasted...
TT:....*ZAP*

What about in the beginning? If time is a manifestation of the universe then before the universe there was no time. Therefore at the very start wouldn't T=0 ? If there was no time before zero then there wouldn't be <0 . (Gee, I hope I got this right?)

It is right if, and only if, time/the universe has a beginning. (Big Bang theory or equivalent) If these theories are correct, then travelling to time 0 would also be impossible as at that moment the size of the universe was also 0. You wouldn't fit.

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?
I dont necasarily agree with that but Just watc Terminator then it dosent make sense how did the guy Invent the Terminators? :confused:

Time is one-directional. You can speed forward, but you can't go back.

Gonna have to dig out my theory of reverse and forward time travel i see.

As I said before, it is not theoretically impossible to go back in time. That doesn't mean it's practical. It's theoretically possible that if I run at a brick wall I could pass through it unscathed. I don't think the lack of time travellers proves anything, is the point I was trying to get at. I just like to bring up the running through a wall as often as possible


There is enough mysteries in human history to explain easily for time travellers i think.

The simplest answers are often, however, half wrong.
Time is not just a way of describing a point in a continuum. It is also an absolute ordering of things within that continuum. Yes I can define any moment as moment 1. But this does not change the fact that things have occurred before moment 1. and things will occur after moment 1. We have two different types of time. (A series and B series from McTaggert). One is as you describe. Points that are defined. The other is as I have described a proghression along a defined sequence. As your definition does not describe a logical space within which movement would be possible, then no backward time travel would be possible in it. Mine however is an ordered set, so movement any direction within that set is theoretically possible.

No. you don't win. You get half a medal only.


very nice. good job, old chap! quite right. Time is, as far as we can tell, a dimension, just its a time dimension whereas the other 9 or 10 are spacial. Perhaps one of the extra theorized dimensions is a time dimension that is inaccessible because it is curled into a Planck length-sized ball...

either way, to the originator of this thread: do not, i repeat, do NOT ever make sweeping absolutist statements like that when it comes to science. very few scientific statements are "laws" that are universal and unalterable. the nature of spacetime is not one of these, and you would be well advised to study the history of science and observe how it has continually altered its perceptions to fit the data.

It is right if, and only if, time/the universe has a beginning. (Big Bang theory or equivalent) If these theories are correct, then travelling to time 0 would also be impossible as at that moment the size of the universe was also 0. You wouldn't fit.

Sure you could, if you don't mind being squished into a one dimensional nothing.:)

So time is at least one directional, could be two. Could time travel in any other direction (sideways)? Does direction imply dimensions? Does time, as a dimension have dimensions of its own?

Is time only two directional, forward and back? :eek:

Not necessarily, but would you notice if you moved sideways through time.
(A cookie for anyone who can identify the song reference)

We can "travel" through time. Just no in the ways your used to. You physically move to new york or japan.
We travel forward in time by letting time pass. We can speed up or slow down our forward motion through time (the faster an object is moving, the slower time passes for it - relatively). You can even stop moving through time, by moving at light speed (or would that count as moving infinately fast through time? depends whos time you're talking about).

As for moving backwards, who was it that pointed out that we can look through telescopes and see the past. We're observing things that happened. Heck, most of the stars you see in the sky could have blown up thousands of years ago, and you'd never know. We're observing the past.
There's some physics theories that deal with this, and talk about..um...not being a physicist I didn't remember the terms. I think it was the "white cone" which is, effectively, our past. And another cone which is our future. We can affect the future (go on, try it!), that's entirely in our hands, so you can't blame anyone for your future screwups but yourself. The white cone, which represents the past in this discussion, however, is fixed. Can't be changed. Which neatly explains why you *can't* punch yourself in your nose, there is just this...force...which will ensure that it won't happen. Called causality (yes, seriously).

This does not mean that time travel isn't possible, far from it. It just means that if you travel backwards in time, you can't change anything. You can't turn up at the american declaration of independance, if you weren't originally there the first time. You can't punch yourself in the nose, unless when you were little you punched yourself in the nose. It doesn't mean that you have no free will, you potentially can run around like a crazy loon doing whatever you feel like, who's to say that's not what originally happened. And when you get back to your time, you could even check if you made it into the history books. But if you never got a broken nose your whole life, it's impossible to go back in time and break your nose. Causality will stop you.

Yeah, I know, it seems weird. If I had a time machine, really, what's to stop me walking over and punching younger-me? What, exactly will stop me? I understand gravity stopping me from jumping buildings. I don't really understand what sort of force would stop me punching young-me. I don't understand how maths can limit my options. But I don't understand the concepts well enough, anyone showing me the maths for gravity wouldn't convince me either, if I grew up in zero-g.

And...I suspect...the way causality stops you doing these things is because time travel happens to be impossible. But that's just my suspicion.

Time is the inability to percieve everything at once.

I'm not sure where I heard that. I might have made it up.


As for traveling through time, it has been determined that if time travel is possible then you will only be able to travel back as far as the point where the time machine was invented. So can we travel "back" in time? Not until the future.

As for traveling through time, it has been determined that if time travel is possible then you will only be able to travel back as far as the point where the time machine was invented. So can we travel "back" in time? Not until the future.

How did you determine this? :confused:

The simplest answers are often, however, half wrong.
Time is not just a way of describing a point in a continuum. It is also an absolute ordering of things within that continuum. Yes I can define any moment as moment 1. But this does not change the fact that things have occurred before moment 1. and things will occur after moment 1. We have two different types of time. (A series and B series from McTaggert). One is as you describe. Points that are defined. The other is as I have described a proghression along a defined sequence. As your definition does not describe a logical space within which movement would be possible, then no backward time travel would be possible in it. Mine however is an ordered set, so movement any direction within that set is theoretically possible.

No. you don't win. You get half a medal only.

theoretically possible....so that means that in theory there is a possibility that it could be maybe done...but you're not sure...well i say you dont get any medal period, its easy to "maybe" prove something...like in theory your mother is not fat, evidence shows otherwise but in theory it is possible that she is not those things

As for dimensions well u should all watch the lil documentary on the PBS website with mark greene, explains the basics well

How did you determine this? :confused:

It was on a program I was watching on PBS. The loose outline of it all is that to travel through time you must expand a wormhole. The time travel device will be the machine that will expand the wormhole. You can only expand a wormhole in the present and wait for the future to come to you. You cannot use something before it exists, not even a time travel device.

It doesn't matter though. Stephen Hawking doesn't think time travel is possible and I see no reason to disagree with him.

Just as a point, what if time is not linear, what if the infinite universe theory is correct? You could go back in time, kill your whole family, you as a child, the king of england, jesus himself, and time as you know it WOULD NOT CHANGE! But time in itself is only our perception of the universe, which in itself is our view of the mixing of different dimensions. "The Big Bang was not an explosion in space, but rather and explosion of space" I highly doubt that time travel would have a negative effect on your reality.

theoretically possible....so that means that in theory there is a possibility that it could be maybe done...but you're not sure...well i say you dont get any medal period, its easy to "maybe" prove something...like in theory your mother is not fat, evidence shows otherwise but in theory it is possible that she is not those things

As for dimensions well u should all watch the lil documentary on the PBS website with mark greene, explains the basics well

If I argue for a theoretical possibility against someone making a theoretical denial of something, I am meeting them on their own terms. That seems to be a fair thing to do. If you want all theoreticaly possible actions to be instantiated before we consider them as possible, you are denying any possibility of invention. Either we can already do it, i.e. it is instantiated, or it is only theoretical and thereby of no value to anyone ever as my mother may be or may not be fat.
While the facts concerning something are not known, then the only type of discussion possible is theoretical, like it or not.

We, not knowing the fact of the matter, can sit here and theorise about your obsession with fat elderly women, only when you show that you do or do not have this obsession does the theorising become fact.

This also applies to time travel. As, at present, we do not have proof either way, what we have and can discuss are theories.

What if a time traveller who travelled to the beginning of the universe, caused the Big bang by disrupting the quantum symmetry with his presence?

Actually, I think time is non-existent. It's just a human-made concept to bring order to the chaos that is the universe so that we can grasp reality better. The duration it takes for something to change from state A to state B is measured and given a name: second. Or minute or hour ;) That is time - but moving back "through" it is impossible, since it does not actually exist. Events happen and that's it. There is no way to go before the time when the event happened.

That light moves at 300k km/s means that if something is faster than light, it would pass it and see it approaching - just as if you were to pass a biker with your car, decelerated and then watched as the biker approaches you. It's not some sort of proof for the existence of time and so far, nobody has proven that the concept of time exists in the universe or anywhere besides the Human imagination.

Ein Deutscher']What if a time traveller who travelled to the beginning of the universe, caused the Big bang by disrupting the quantum symmetry with his presence?

Actually, I think time is non-existent. It's just a human-made concept to bring order to the chaos that is the universe so that we can grasp reality better. The duration it takes for something to change from state A to state B is measured and given a name: second. Or minute or hour ;) That is time - but moving back "through" it is impossible, since it does not actually exist. Events happen and that's it. There is no way to go before the time when the event happened.

That light moves at 300k km/s means that if something is faster than light, it would pass it and see it approaching - just as if you were to pass a biker with your car, decelerated and then watched as the biker approaches you. It's not some sort of proof for the existence of time and so far, nobody has proven that the concept of time exists in the universe or anywhere besides the Human imagination.

Finally a good reply to this God forsaken thread.

(Please note that I only skim through threads, I'm that much ADD :p)

It depends on which model of time you use, elasticity of fragmentation

Elasticity: All time is consitant, any changes made in the past have already happened, nothing will change

Fragmentation: Any change in the past will effect the future, leading to multiple possible futures from the point at which you travel back to

Also an interesting idea I thought of for this is time being the fourth dimention means that in a 4D universe is one identical to this one execpt there time travel is possible.

Time travel is possible. Going forward is possible. Going back isnt. Unless your Donnie Darko.

Time travel is possible. Going forward is possible. Going back isnt. Unless your Donnie Darko.
You don't actually go through anything. By existing, things around you and you yourself constantly change. This change is what you perceive as the movement of time. But it is actually just your brain that applies it's limited knowledge on reality, so you can grasp it. Time itself is a concept, not a reality and not a dimension. The people who claim that time is a dimension simply want to make the whole process sound more difficult and scientific, than it actually is.

Time travel may be possible in the future but the consequences of such would be tremendous. Imagine if you went back to the dinosaurs and stepped on a mosquito and that mosquito had actually bitten and killed a dinosaur and so on and so fourth. Even the slightest change of the space-time continum could have very, very, very drastic consequences. Every movie about time travel has raised this issue. It's like AI. Many works about AI have protrayed it to be a very dangerous thing and that is very true. The Terminator series & the Matrix series provide the worst case scenario's for AI. I think that we ought to learn from that, albeit they are movies, and just not do AI. The same goes for the time travel issues, we should simply just leave it be.

After explaining why time does not actually exist, what makes you think that time travel would work? Given that time is a figment of human imagination, how can one travel back or forth through it? The simplest requirement for time travel would have to be time as a medium that can actually be travelled through in either direction.

Imagine if you went back to the dinosaurs and stepped on a mosquito and that mosquito had actually bitten and killed a dinosaur and so on and so fourth.

Its ok to admit you got that from "The Simpsons"

Its ok to admit you got that from "The Simpsons"
"you go squish now"

It's also possible that if we were somehow able to go backwards in time, then we'd simply erase our memories doing so - our aging would reverse, we'd run our life in reverse. Go back too far, and you'll pop back inside your mum and cease to exist.

I read somewhere that if we could create a wormhole, hold one end steady, then accelerated the other end to the speed of light, bringing it back to the original start-point, then entered, we'd step through the event horizon, and instantly be sent forward in time.

Its ok to admit you got that from "The Simpsons"

Actually that reference is older than the SImpsons, it harks back to a Sci-Fi short story by Ray Bradbury, called
A Sound of Thunder (http://www.sba.muohio.edu/snavely/415/thunder.htm) IT'll take you ten minutes to read...

Firstly, I'm in the "what you go back and do, you already came back and did" camp, regarding how time travel works. Closed time-like curves, and all. I'm Ok with spontaneous creation of alternate universes upon your 'appearance ' back there, so you have your own universe toddling along, now without you, and the one you spawned around your enrtry at that point, but only if the creation of a universe is mass+energy neutral (i.e. it all cancels out in the quantum foam, whichis what some people think works with the Big Bang and all) or the mass+energy load of the universe you left (at the point you left) is used to form the universe you create. In the latter case, there'd be no universe immediately after the traveler went back. These reasons are why I believe all events are 'fixed', including the ones that lead backwards and forwards independant of the basic structure of the universe.

(There, there simultaneous existence of a time-traveller's mass and energy at the same time as the mass and energy's own 'previous' existence is, again, quantum foam on the grand scale of things. It all goes back to normal once the TT passes his departure point, or leaves the past and rejoins the future timeline.)

c.f., also, the "billiard balls and wormhole" thought experiments, where the emerging billiard balls deflects its past self into the wormhole entrance in order to emerge to deflect in the past to deflect its past self. (As opposed the one where an emerging ball deflects itse;f fom ever going in. The stable situation is where it self-reinforces.)

I dont necasarily agree with that but Just watc Terminator then it dosent make sense how did the guy Invent the Terminators? :confused:

When it comes to fiction, I can take it or leave it (e.g. the Timecop's "if matter meets its cousin from across time it goes all 'bleurgh', despite the obvious probably that skin and even bone cycles itself and isn't the same matter... :)) but I have found that there's an interesting fictional loophole to the Terminator series.

With the exception of John's father, all those sent back could have been reprogrammed to maintain the future that does (as of T3) occur, including false information. We see how T3's T800 gives a false lead to John & his girl to keep them safe when things go to pot. What if the information about the designer creating Skynet, and the chip and hand being used to do so even without the now sympathetic designer's complience, was given in order to force the situation where the creation of Skynet and the T-range were moved to the people who (even originally) did create the whole problem as seen in T3. (And at the time now given in T3, rather than the one give in T2/T1.)

John's father might have gone back with misapprehension, perhaps deliberately misinformed, or else ordered to convey the information that John knew Sarah had been told (knowing, by then, that the information that was given would lead up to the what happened). Why did he do so? Why did the Ts come back knowing that their actions and respective destructions were preordained? Because human and machine leaders/intelligences alike knew that these things had had happened and neither human nor machine forces were willing (or able, due to fate) to destroy the universe by directly countering it 'just' to win the war. After all, humans and machines were both still alive at all times when travellers were sent back and thus had not lost, so perpetuating that situation was surely better than trying (against the will and temporal inertia of the universe) to alter things that, in a butterfly cascade, could have caused them to not exist at all.


It is much more complicated to explain, but I essentially believe that one possible 'solution' to the formula that is the Terminator series is that there are no paradoxes. We don't see time changing (like we do with the Amazing Disappearing Marty McFly from Back To The Future) so why should we believe it does?

That's what I think... The fact that it coincides with what I think happens in the real world (in principle, at least, if not as a carbon copy complete with the Rise Of THe Machines situation... :)) is purely coincidental, you know. ;)

It's also possible that if we were somehow able to go backwards in time, then we'd simply erase our memories doing so - our aging would reverse, we'd run our life in reverse. Go back too far, and you'll pop back inside your mum and cease to exist.

I read somewhere that if we could create a wormhole, hold one end steady, then accelerated the other end to the speed of light, bringing it back to the original start-point, then entered, we'd step through the event horizon, and instantly be sent forward in time.Or backwards. It's the device that is used in the 'billard balls' thought experiment.

(It's also one of the forms of time travel aluded to in the "you can never go back earlier than when the time travel machine was made" arguments against seeing Tardii popping up all over the place in history. When you have one end "here and now" and one end "there and now" and make one end artificially younger than the other end and pass through the "young" end to come out at the "normal" end when the "normal" end was still as young as the "young" one, thanks to relativity, is at this moment, then you can only go back by the difference between the two ends, which can never exceed the age of the wormhole-pair since you started messing with them in that way. I think the same applies to the "two infinitely massive/longcylinders spinning" version of the machine, but I'm hazier on those details... :))

Its ok to admit you got that from "The Simpsons"

Of course I did. However, that isn't the only "thing" that displays the problems with time travel. Do they not raise valid points? Hell imagine going back and moving Hitler's gun to a different location. He might never had shot himself and that would have been very, very, very, very, very bad.

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?

while i do believe it to be impossible to travel in time, those paradoxes can be eliminated. An illustration of what i mean is the movie '12 monkeys'. think about it as what has happened has allready happened, even the actions of someone from the future when he went back in time. Therefore you can't change the present by going back in time.

The practicalities of both forward and backward time travel have been solved and are commercially available.

There's one on eBay right now: Clicky Clicky (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=88433&item=5569364441&rd=1)

Read about Retropsychokinesis <<--{Click} (http://www.fourmilab.ch/rpkp/)

Traveling back to this time worked for me. Oh, and by the way, that whole Iraq thing worked out just like Cheney planned.

Traveling back to this time worked for me. Oh, and by the way, that whole Iraq thing worked out just like Cheney planned.

LOL. I figured humanity would have destroyed itself before time travel was possible.

Two possible solutions.

1) The multiverse theory, (which, as far as I know, is supported by the majority of the scientific community {If anyone has seen a paper or research disproving it, let me know}), is true and another you would remember it or

2) The universe wouldn't let you do something as stupid as that and either you would be prevented from hitting yourself or you would hit yourself so hard that the young you would lose all memory of the incident. The universe would protect itself.

Ein Deutscher']What if a time traveller who travelled to the beginning of the universe, caused the Big bang by disrupting the quantum symmetry with his presence?

Actually, I think time is non-existent. It's just a human-made concept to bring order to the chaos that is the universe so that we can grasp reality better. The duration it takes for something to change from state A to state B is measured and given a name: second. Or minute or hour ;) That is time - but moving back "through" it is impossible, since it does not actually exist. Events happen and that's it. There is no way to go before the time when the event happened.

That light moves at 300k km/s means that if something is faster than light, it would pass it and see it approaching - just as if you were to pass a biker with your car, decelerated and then watched as the biker approaches you. It's not some sort of proof for the existence of time and so far, nobody has proven that the concept of time exists in the universe or anywhere besides the Human imagination.
I would agree with you except, according the Einstien's Theory of Relativity (I forget if this is the general one or the special one), space could not exist if time didn't. Becuase time and space aren't separate, and "space" isn't really emptiness. Instead space-time is like a fabric than can be distroted by forces like gravity.

It's the general one. special one is about the speed of light.

Time travel may be possible in the future but the consequences of such would be tremendous. Imagine if you went back to the dinosaurs and stepped on a mosquito and that mosquito had actually bitten and killed a dinosaur and so on and so fourth. Even the slightest change of the space-time continum could have very, very, very drastic consequences. Every movie about time travel has raised this issue. It's like AI. Many works about AI have protrayed it to be a very dangerous thing and that is very true. The Terminator series & the Matrix series provide the worst case scenario's for AI. I think that we ought to learn from that, albeit they are movies, and just not do AI. The same goes for the time travel issues, we should simply just leave it be.
This is not necesarily true. You could go back and time and theoretically do whatever the hell you want and nothing in the future would change. Becuase when you go back, you're not actuall y changing anything. that's just the way it is.

Nothing in 2005 would change (if we could time tavel back) even if all 6.45 billion of us went back and did whatever the hell we felt like in the time of the dinosaurs and then came back. Everything just fits together like a puzzle. This is the way time travel happens in the "Hitch Hiker's Guide to the Galaxy" sereis by Douglas Adams.

Do yourself a favor and stop looking at time travel as terminator or back to the future and more like sliders.

You rip a hole in the space-time countiuem by seemingly going faster then light. (This is probably moreso the impossible feat, not time travel in itself.)

Because the universe cannot catch-up with you you "slide" into a differant exsistance, assuming you could control what point in "time" you arrive at, you could go there and meet your ten year old self or whatever.

This has no effect on you because you are outside time now, time in the sense of your past, that 'slider dimension" is somewhere else, probably a place you'll never be able to reach again as to do so would mean time retreating.. which I would assume would mean you would have to go SLOWER then time. Try figuring out that one.

So now you're in a new universe because space-time has folded around you and made you a part of some neo-verse, where you and your ten year old self are in the same place at the same point in "time". Your actions and exsistance now effect only this plain, not your previous one.

Time does not exist. Time is only a way to reference the position of your person in comparison to the sun and other stars, via revolutions and rotations......You can call anypoint in "time" 1 b.c. Now for those of you who are going to bring up the age point. All that is is a way to reference what all is biologically happening within your body. More growth than decay. or more decay than growth. Maybe equivalent growth and decay. Bwuahahaha I vin!

Based on this logic, distance doesn't exist either since any distance can be called 1 inch. Time is neccessary for things to exist as it provides a state of existance for them. You should give a read to "A Brief History of Time". Kind of dull but it beats pseudointellectual yammering.

I like the multi-verse theory, not because of any of the math or theory, but because it has every possibility in every combination. The possabilities!:)

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?
This is why we watch Back to the Future. Well that and the cool soundtrack. :)

This has been alluded to in a previous post, but basically, if there are multiple worlds/timelines/dimensions, then the biggest paradox of all - the grandmother paradox - breaks down, as you simply create a new world by killing your grandmother and she remains healthy in your original world.

Some scientists believe there MUST be multiple worlds in order to account for being able to predict where quarks will move. Or something like that. It was something I read a year or two ago.


well, say in 1000 years, people come back to today, does their world 1000 yrs from now, stop, or is it going on alongside our time simultaneously? Time travel is much too fucked up and convoluted to understand for me.

Some people say it will create an alternate universe, other people say that it will change the one existing universe (which is where the paradox argument is coming from) Other people favour the closed loop idea, where you can't change what happened, the future is the way it is because you went back.

Ein Deutscher']That light moves at 300k km/s means that if something is faster than light, it would pass it and see it approaching - just as if you were to pass a biker with your car, decelerated and then watched as the biker approaches you. It's not some sort of proof for the existence of time and so far, nobody has proven that the concept of time exists in the universe or anywhere besides the Human imagination.

aw, fer chrissake. NOTHING TRAVELS FASTER THAN LIGHT. period.

and to the poster a while back: the universe at time 0 had a radius of 1, so it was not squished into nothing. too tired to elaborate.

i dont think you can go backwards through time, but you can slow time down, by accelerating as close to the speed of light as possible almost 0 time elapses for you, while on earth it takes longer, you can go around the earth at 99.9% of the speed odf light27 trillion times, and land sometime near 4000 AD, i think, and you are only as old as the time you spent flying around the earth, plus your current age

aw, fer chrissake. NOTHING TRAVELS FASTER THAN LIGHT. period.

and to the poster a while back: the universe at time 0 had a radius of 1, so it was not squished into nothing. too tired to elaborate.
That's not true. Light can be decelerated to a much slower speed than 300k km/s. My example was just hypothetical anyway. I know myself that past the speed of light, mass becomes infinite - according to Albert Einstein.

I have figured it to be impossible to go back in time becuase of the paradoxes it would create. If you went back to when you were 10 and punched little you in the nose, how could you(from the future) suddenly remmeber that?
You would already remember it even before you went back in time. :D
That one actually works.

This one doesn't. You see your girlfriend die, build a time machine, and go back and save her. But then she never died, so you didn't have to go back in time to save her. Since you didn't go back in time, she died. Since she died, you went back and saved her...... etc.

This one's worse. You go back in time and kill your mother before she bore you, preventing yourself from being born, and therefore preventing yourself from going back and killing your mom. Because you were born anyway, you go back and kill your mom, preventing yourself from being born.....

*sigh*

Paradox's are fantasy. If you manage to go back in time, you are not the person that you were at that time. If you shoot your old self, you wont die. What would kill you? Time isnt a one track. You are a hunk of mass that can control itself. Killing your old self doesn't put a bullet into your body. You are independant of time, quite simply.

Ein Deutscher']I know myself that past the speed of light, mass becomes infinite - according to Albert Einstein.Can't remember if it's Einstein or a contemporary (Lorentz?) but mass beomes infinite at the speed of light due to division in the appropriate term by "c^2 - v^2". Where velocity = speed of light, that comes out as zero and the division says "infinite mass", similarly "infinite length" and "zero time".

(Because it's relativity, this also means that if you observe your original standing point from the object going the speed of light, everything is 'normal' on the object, but the universe has all those odd properties... Assuming you can deal with the fact that the entire universe is coming past (and through) you at the speed of light, which doesn't sound particularly healthy... :))

Once you're past the speed of light, the equation isn't a division by zero, but a division by a negative. Think of what happens in a graph of 1/x as you go zero 'y' from the infinite+ side of 'x', pass through zero (zoom up to infinite+ 'y', come out of infinite- 'y') and then you approach 0 effect again, but from the other side of the line, as you approach infinite- 'x'.

Essentially, this means that things going faster than light and things going slower than light are possible, but passing through the speed of light is not. The things going faster than light (theoretically tachyons, they say) are also affected by having negative versions of mass, time passing, length, etc, that make them act like particles going forward in time, but in reverse... erm... as it were. If a normal particle X decayed into normal particle Y and a tachyon (T) and then T decayed into normal particles A and B (I've no idea what particles X, Z, A and B are, it's just an example), something like the following might be seen:

---X--->(1)---Y--->
/
/
T
/
/
L
(2)---A--->
\
`-B--->

---Time--->
i.e., the Tachyon, goes backwards in time. It [I}looks[/I] (to an observer) like there's a spontaneous production of T, A and B, at (2), then T then 'happens' to hit X at (1) and produces 'Y'. Because T left 'backwards' with negative mass, massX=>-massT + massY or massX + massT => massY, and the same with other properties, so it all looks to add up. I think, anyway... ;)

This is just one theory. Might be discredited by now, it's been a while since I learnt about this stuff.

This one's worse. You go back in time and kill your mother before she bore you, preventing yourself from being born, and therefore preventing yourself from going back and killing your mom. Because you were born anyway, you go back and kill your mom, preventing yourself from being born.....

*sigh*

Paradox's are fantasy. If you manage to go back in time, you are not the person that you were at that time. If you shoot your old self, you wont die. What would kill you? Time isnt a one track. You are a hunk of mass that can control itself. Killing your old self doesn't put a bullet into your body. You are independant of time, quite simply.

I don't agree with either of these POVs. (As in, I feel neither fulfill the combined 'aesthetic' and scientific qualities that I seek, not that both are obviously wrong, because I accept I could be wrong...)

My view boils down to:
A) I believe in fate, the whole universe mapped out (from a POV encompassing all of time, space, whatavyer, and I accept a supreme being may sit at this point but I don't specifically invoke one) and that all that will happen will happen
B) If time travel is possible, and is accomplished (as in closed time-like curves, not just time dilation) these loops are set in stone in the above 'map' and all loops in time that do occur are self-consistent (even self-fulfilling) because that's how it all clicks together.

i.e. "Whatever you go back in time and do, you have already been back in time and done". If the 'grand equation' of the universe included the creation of a time-traveller who went back in time and changed things, the equation would not just 'flip-flop' between mutually exclusive paradoxes, but would perhaps find that (for example) because of an old injury, the traveller suffers a small muscle spasm at the time he tries to shoot at himself and, rather than killing his past self, he causes an injury. Yes, that old injury. Thus the 'grand equation' is in a consistent state.

What solutions would arise to allow a consistent closed time-like curve to encompass the attempted killing of grandfathers and mothers I don't know, but (in my view) it'll resolve if possible and wouldn't 'settle' to form a universe if it doesn't. Perhaps the 'quantum foam' is the mechanism by which 'randomness' thwarts the (supposed) plans of time-travellers, but that takes more explaining that I fear I have time for here. And I like this idea better than "new universe created" (unless there are no problems 'creating' that much mass and energy because it all adds up to nothing anyway), the 'flip flop' universe that shuffles between two realities, even the "mind over matter" one that Chellis suggests (because I believe that 'mind' is a function of the matter and energy, i.e. the universe, and is thus still determined in the 'grand plan'. Fatalistic, that's me... But I would be, wouldn't I..? ;))