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Time Travel

  1. Feb 17, 2004 #1
    I am curious to see what your opinions are on the odds of Time Travel accually being achieved...

    under what circumstances do you think it would be possible?

    And those of you who do believe it will be possible in the future, how much longer until it is possible?
  2. jcsd
  3. Feb 17, 2004 #2


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    Based on current theory, time travel to the future is quite possible. However, travel to the past is not.

    When technology is advanced to the point where we can go to other stars, the we will be able to travel to the future.
  4. Feb 17, 2004 #3
    Possibly sooner, depending on your definition of time travel! Aside from the obvious analogy that we're travelling to the future right now, one could also consider stasis to be 'time travel' from the perspective contained within the field of stasis. However, I believe you're correct that there would seem to be no way to travel back in time. Not only is this true, but it is logical. To travel back in time is absurd, to travel forward is not. Then again, consider what was considered 'absurd' 50 years ago compared to now. ;)
  5. Feb 17, 2004 #4
    Time is down to sequence and duration, so under our current paradigm it would not be possible. Yes you can travel into the future, as we are all doing at the moment.
    Hello all you time travellers !

    It's possible that one day it may be possible.

    How to achieve Time Travel ?

    It you take a clock - a very simple clock with a direct drive from a motor - and you reverse the battery, the clock efectively runs backwards.
    That is what would be required to time travel, but slightly more complex.
    You would have to find a way of reversing the natural sequence of events. Low pressure flowing towards High pressure - you would have to effectively reverse the laws of thermodynamics.
    If that was possible, and you could encase yourself in a bubble of reversed thermodynamics, then maybe you would get the desired effect.

    As for when it would be possible. If it is possible in the future, then it already possible now, assuming we were interesting enough for somebody to travel back and observe us.
  6. Feb 17, 2004 #5
    Methods for time travel.

    There are many theoretical methods of time travel.

    The first is simple: Just freeze yourself, and then thaw when the time is right. That could have problems, though. The cryogenics could mess up, and you might be stuck in liquid nitrogen for near eternity without waking.

    Another method is very clever, but quite time consuming. You set off on a relativistic flight with a wormhole, and the time dilation causes you to "skip" elapsed time to a point where you stop. The wormhole has two connections: The one back in the past, and the one with you. You can stay in the future for as long as you wish, and you can enter the wormhole back to the past when you are ready. You may have to wait a few decades before you finish the timelike-trajectory.

    There is one more method I know of: Closed timelike curves. Apparently when you got in a circle, you'll end up where you were a little while later. If you went fast enough, you'd be back at where you started before you went, so you would achieve a fraction of a step into the past. If you kept on doing so, you could apparently go thousands of years or more back to earlier events. Unfortunately, you would need cosmic string, and other exotic materials to achieve such a Back-to-the-Future-esque flight.

    The latter two methods were described in Stephen Baxter's novel, Ring. Methinks a grand novel, and you should read it sometime, along with the others. Have a long life and prosper well.

  7. Feb 18, 2004 #6
    thnx flashheart =]

    for those of you who said that it is only possible to travel to the future, why is it obsurd to travel to the past? and have you read hawkings lecture on space and time warp?


    i think what he's saying here is that its possible to go back in time in a similar method that flasheart said...

    thnx guys, your opinions mean alot to me, and give me better prespective on whats realistic and what isnt...
  8. Feb 18, 2004 #7


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    The arrow of time is linear and flows in one direction only for a number of reasons. Depending on how you see it, the 2nd law of thermodynamics is a reason or a manifestation of that.
    He doesn't mention it and warping space is not the same as warping time.
  9. Feb 18, 2004 #8
    If time travel were possible in the distant future, then the chances are we would already know about it.
    There would certainly be at least one individual with a wicked sense of humour who would have influenced our history in some small way.

    A dinosaur dug up and found to be wearing a Rolex (taken from a book I read once) or a Roman soldier with a bag full of 20th century coins.

    I cannot believe for one moment that if time travel was possible, that there would not be some indication of it. That it would be so restricted or policed to never let idiots leave things behind.

    Unless, it's a conspiracy and our governments already know of its existance......
  10. Feb 18, 2004 #9
    ok, well one more thing, there is this thing i read->


    i donno, it seemed pretty persuasive to my neutral mind set on the matter.

    it speaks alot of einsteins theory on relativity, but i really didnt understand much of the math, or much of the connections they made, leaving me helpless in attempts to analyze the matter...

    if anyone has run across anything like this themselves, or if they have taken the time to read a little bit of the link i produced, i would like there views on it...

    i mean, until there is some evidence of it (which i have come across, if you search for 'john titor' on google) i really have no other choice but to get on with my life... since i dont posses the knowledge to figure it out myself... i am determined to understand the nature of time better though from your replies...

    and, if time travel to the future is only possible, is there anyway to go back? or is that dependant on your method of time travel?

    if there is it 'seems' to me this method could be manipulated to travel to the past...

    i am guessing not since there is no scientific evidence supporting time travel to the past...

    thnx guys.

    1love to the peeps on this forum -_-;;
  11. Feb 18, 2004 #10
    also, besides a brief history of time, are there any books you guys could recommend for a good start on a better understanding of time, space-time, and good detailed information on space-time relationships with a minimal amount of mathematics?

    and maybe a tutorial on how the Minkowski Diagram functions?

    also maybe something that would enable me to understand the mathematics in books based on space-time? (this is for if there is no book that could possibly fully explain to me the nature of space-time without mathematics)

    a book that when im finished reading i will say to myself 'hmm, this makes sense' ?

    thnx thnx thnx
  12. Feb 18, 2004 #11
    Here's a link to some stuff that may be of use.

    One aspect of time travel that should not be overlooked is the amount of energy in the Universe.
    If you travel back in time from now, when you go to, that point in time will exceed the total energy in the Universe by the amount of energy you contain. This may cause a few problems.

    It may be that if time travel is possible, you can only go into the future, and return. And in doing so ensure that you maintain the total energy.
    You would have to isolate your energy now and ensure it doesn't alter, even by one photon, until you arrive at your destination time. This would mean that your own time line would have been frozen at your point of departure.
    The result being that you could go into the future, but nothing of you would exist in that future, so the future you see wouldn't be reality.
    When you return, you cannot be sure that anything that you experienced will actually happen, because your time line will be restarted which will alter some part of the future.

    Hope that's clear.
  13. Feb 18, 2004 #12
    hmm, very convincing man! this makes sense to me thnx...

    hmm... but if your original timeline freezes doesnt that insure that there will be no energy imbalance when you return?

    besides this, wouldn't you radiate energy while in the future? and wouldnt this radiated energy cause the disturbence in your own timeline when you return (like a lower count that what was, and you think there could be some overlooked law of time travel that regulates this energy mismatch somehow that we dont now of because time travel has never been attempted?)? if this is the case, why bother with the future energy isolation seeing as you will be altering the energy balance in your timeline when u return anyways? or would the mechanism you have have to funnel the energy back to your timeline somehow?

    thnx 4 link and reply -_-;;
  14. Feb 19, 2004 #13
    When you reached the future you would start to radiate energy, you would also be absorbing energy as well.
    When you are ready to return to your own time, or any point in between, you would need require a special device, the Localised AWolf Time Travel Equilizer ( LATTE for short ) This device would force you to loose or gain enegy to match the amount you arrived with, thus maintaining the balance.
  15. Feb 19, 2004 #14


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    FYI, John Titor is either a hoaxster or is mentally ill. I haven't read enough about him to know which.
  16. Feb 19, 2004 #15
    aaaaaaaaaa that was uncalled for. but i guess i see your point awolf...

    but i think it is the lack of knowledge we BOTH have on the matter that it turned into a mockery...

    i was on your level, but apparenty you were full of it to begin with =]

    and arent we being a tad narrow minded russ?

    doubt has always been a method to suck humans into a believe, but the consideration shouldnt be ignored completely. if you had read more and given more info instead of stating he is mentally ill and what not then i would have respected your opinion without writing this.

    dont get me wrong, i still respect your opinion regardless of your lack of interest and research on the guy...

    the way i see it you have looked at the cover and judged...

    but apparently he has made a prediction that there will be a civil war in the USA between the dates of 2005 and 2008.

    if it is a hoax, the possibility of a civil war breaking out is still possible, regardless of his prediction.

    one simple reason: the 'bombings' of the world trade centers and everything that has come from that...
  17. Feb 19, 2004 #16
    Elibol, this is all pure speculation as there is no proof that time travel is possible.
    The reverse is also true, nobody can provide proof that it isn't.

    Anything is possible until proven otherwise, and even then it may still be possible.

    An interesting quote I read recently on http://groups.msn.com/TheoreticalPhysicsCosmologyandotherSciences spoke about UFOs and that they travel in time rather than space. The quote was from a guy called Sherman

    'they' don't travel through time but rather "around it".

    This adds another dimension (no punn intended) to time travel.
  18. Feb 19, 2004 #17
    well, i can certainly say i like this reply better than the other one... i am not trying to prove anything to anyone with no evidence or scientific observation man...

    but when my curiousity and interest in something is mocked... i feel pretty violated... thnx for the info, this is very interesting as well...

    yo, where in this link is that quote?

    now that i think of it, around time? i mean, i dont even really have a visual depiction of what traveling thru time would look like, and around is just a term relevant to space...

    that doesnt flow yo...

    imma take this to the philosophie forum -_-

    i think it has evolved out of the context of being realistic at this point...
    Last edited: Feb 19, 2004
  19. Feb 19, 2004 #18
    Time travel would likely be instantaneous from your perspective, since you're not actually moving in any dimension except time. Speaking of which, I've seen a lot of comparisons of time to space. IE, if we can move both forward and backward in space, why can't we do the same in time? It's been explained to me on another thread that time is not a spacial dimension.

    In regards to going 'around' time, I believe the reference is similar to the standard two-points-on-a-piece-of-paper example for describing how a wormhole might work. If you haven't heard of it before, it goes like this:
    Consider two dots on a piece of paper. What is the shortest possible distance between these two points? The answer seems simple, a straight line, right? Wrong. The shortest distance is to fold the piece of paper so that the two points touch. The distance is now zero, and you can travel there without moving! The question is, how to bend spacetime such that two desired points connect. Stephen Hawking seems to have a lot to say on this subject... I suggest finding some of his literature if you're really interested in the wormhole idea.

    In regards to:
    In order to go fast enough that you arrive just as you depart, you would have to be travelling at an infinite velocity. In other words, you don't travel you just are. As if that doesn't seem difficult enough, in order to arrive before you depart, you'd have to go faster. In other words, this theory assumes it's possible to go faster than infinite velocity.

    Finally, one last note. In regards to:
    Hmm... hope I don't offend anyone but... how about that Bible? Or perhaps... Stonehenge? Similar such features may turn out to be exactly those kind of 'traces,' but we'd never suspect it because we're so used to hearing about them.
  20. Feb 19, 2004 #19
    The originator of the time-travel method resolved the problems of infinite velocity by giving the timefarer hyperdrive, for both interstellar travel and complex trajectories. Remember, faster-than-light travel is spacelike, not timelike. If one went in a circling spacelike trajectory, he could construct closed timelike curves, with the abnormal effect of going back through time.

    Anyway, this system is impossible with our current technology. I mean, where in the universe are you going to find cosmic string? I guess I'll leave that for astronomers to answer.
  21. Feb 19, 2004 #20
    my apologies if my attempt at humour didn't go down very well.

    Curiosity is what makes us what we are, without it we wouldn't have even got to the stone age.

    Here's the link to the quote. It's somewhere near the bottom.

    By asking questions and proposing any solution or method to time travel puts you right at the forefront. Nobody has a working or workable solution - not the last time I looked.
    It was not intended to be a mockery, and I still think the thread is valid.
    You made a very valid point, that if the total energy is to be concerved, then it must work both ways. It proves that you thought the problem through. If only everybody was the same.

    Too subtle, ite would have to be something far more obvious.

    A better example would have been the city gates in Alexandria. Built on the orders of Alexanda The Great, they were hydrolic with a pressure plate mechanism - now that was cute, but not an indication of time travellers.
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