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Time Travel

  1. Mar 26, 2003 #1
    now we all know that time travel is a very controversial subject. I believe that it is possible and am actually writing a research paper on it. I have a theory, however, that if you did travel into the future you could never see yourself or interact with yourself. If you went into the future than you would not exist in the future until you returned back to your present. Therefore, you cannot ever interact with yourself in the future. The End. I would love for people to email me to discuss time travel and other things so feel free to respond to this thread and email me at shakastar@cool-ideaz.com
  2. jcsd
  3. Mar 26, 2003 #2
    Right, that would only be the case if retro-time travel were impossible. If you travelled 20 years into the future, then traveled back to a point even 1 second after you first left, your time-travel event would be in the future of your now, so in 20 years, two of you will exist. Does that make any sense?
  4. Mar 26, 2003 #3

    yes i can see what u mean, but...hmm....didnt think of it that way....good job! haha do u believe that time travel does exist? ill think of something dont wry :wink:
  5. Mar 26, 2003 #4
    Actually I'm not sure what I believe anymore. So... confused. Too... much... information. Can't... form... complete... sentences.
  6. Mar 26, 2003 #5

    lol i know how u feel. I replied to some of your other posts. Just so you know. Oh and does my theory sound sort of a little bit kind of logical?
  7. Mar 26, 2003 #6
    Yeah it does but like you said this is a controvertial subject. But go for it man. Just remember to narrow the claim your thesis statement makes and back it up with sound ideas. But you already know that, right? :wink:
  8. Mar 26, 2003 #7

    Of cooooooooooooarse i know it haha how old are u? im 16 sophmore in highschool
  9. Mar 26, 2003 #8
  10. Mar 26, 2003 #9
    If you travelled to the future you would not exist in the time from leaving to arriving, because you disappeared in the past and the event of you going back hasn't happened yet. What you are talking about is a splitting in two of yourself or of the timeline. It's a common theme about not being able to interact with yourself. If I invented a time machine in the future and tried to contact myself now, something would stop me because, wait a minute.......no I haven't arrived here. The idea is that if there is a single timeline then time travel into the past does not effect it because it didn't effect it the first time because you were already there the first time. Does that make sense? Of course the main problem with time travel is that if you could go back or forward even a day, when you arrived at your time destination you would be at a completely different place because the entire universe has moved. That would be a bit of a problem.

    Raavin :wink:
  11. Mar 26, 2003 #10
    Ok its 12:22 am here. I'm jumping in my time-machine I hit a couple buttons and bam! its now 12:30:00am only one of me exist. The time between 12:22:01 and 12:29:59.99999999..., I did not exist, which is what you said Raavin. Now, I jump back in my time machine and go back to 12:22:01. There is still a time frame where I do not exist: between 12:22:00 and 12:22:01. In that moment of time I'm in the future. If I travelled back to 12:22:01 and I sit here in my room till 12:30:00 I'm going to see myself pop up because my past self is still in the future. I think. I'm getting confused. I think it's time for bed.
    Last edited by a moderator: Mar 26, 2003
  12. Mar 26, 2003 #11
    dude yea im hitting the sack and ill write tomorrow...too...much...thiinking....ahhh
  13. Mar 27, 2003 #12
    You are sitting in the lab next to your machine and ask your lab partner to write a message on a piece of paper which you will read to yourself when you see yourself in your futures past, which will actually be in about 10 seconds. The machine appears and the other you steps out, pulls out the note and says, "Whatever you do, don't get in the time machine". You pull the note from your own pocket and the note reads the same. What happens next????

    Raavin [?]
  14. Mar 27, 2003 #13
    You get in the machine anyway?

    See the only problem I have with this junk is that meeting yourself in the past implies an infinite loop. And I don't believe in infinity outside mathematics.
  15. Mar 27, 2003 #14
    Thing is, if there was only the one time line, you wouldn't have a choice. Something would force you into going through exactly the same steps your time travelling doppleganger went through. Otherwise you wouldn't have appeared in the first place. There isn't really an infinite loop 'cause once the arriving (now) and leaving (future) events are over, the loop is closed. What it does imply though is determinism and that there is no free will. Although it could also imply that we are aware of 'all time' and that we simultaneously choose particular actions along the entirety of the timeline in an instant, or singularity, of time.

  16. Mar 27, 2003 #15
    Right theres no infinite loop for the you in the now, but it would mean that there is an infinite number of you's; an infinte number of 4-D frames.

    Ok stop me if you've heard this one...

    I've been thinking abouttime travel most of the day today and an idea dawned on me. I'm sure this has been considered before, but I'm gonna mention it anyway. Hypothetically speaking, let's say time-travel is physically possible and we somehow develop a way to accomplish it on the earth's surface. As an example let's say someone travels about six months into the future. Wouldn't your arrival point in the new frame be your original position relative to the universe rather than the earth? Afterall it's a jump through space-time, not earth-time. That would mean that our time-traveller would pop up on the opposite side of the sun! And there is no telling how much our solar system has shifted after six months, nor the position of the galaxy. He might end up in the middle of the galaxy. This would make him very upset. He could also jump forward just a few seconds and end up in the earth's core, if he started the jump on the leading side of the earth. This would make him very dead. So I will never volunteer to be a time-travel guinea pig. But seriously folks, this time-travel jibberish is being taken to literally. When it was declared a theoretical possibility, I'm certain that travelling through time like Marty McFly was not a part of the deal. It's really more like "time-cheating," the way I see it. It was stated that a wormhole is a conduit between two distant points in space. That would indicate that you could never end up in the same exact spot you started in. That also means that you aren't going forward in time per se, you're just moving to another point in space faster than conventional means would allow.

    Wonderful. I just destroyed my own hypothesis.
  17. Mar 27, 2003 #16
    could you kill your parents before you where born

    I rember this on the old PF it wnet soemthing like this:
    If i could go bakc in time kill my parents years before i was born what if anything would happen.
    I thought it was rather intresting to see what peopel have to say now.

    I think it would break time into two outcomes
    First out coem is where you exist but you go bakc in time and kill your parents undoing your existance and then the second out come comes into play where you dont exist but that immedatly ends becuase if you dont exist you cant kill your parents. So you do exist becuase yu cnat kill your parents but since everything goes the exact same way you kill your parents agian...this results in a loop between outcome 1 and 2 but no one would know and now ladies and gentle men i have a headache...

    I merged this into the current thread to avoid the clutter of multiple threads covering the same topic.

    Last edited by a moderator: Mar 27, 2003
  18. Mar 27, 2003 #17
    This topic is being discussed in a couple different threads. Perhaps we should make a separate sub-forum solely devoted to Time travel...?
  19. Mar 27, 2003 #18
    I don't think so. When both event are over, they are over. There would only be two yous if you only made 1 trip. Maybe I'm wrong. The other bit about your spatial position, I mentioned further up the thread.

    I must admit I'm quite chuffed with my time singularity idea. I might think about that some more.

    This is all just a bit of fun. The paradoxes just illustrate the point that time travel is impossible. I like working on things that suspend disbelief in a sci-fi context though.

  20. Mar 27, 2003 #19
    Well, what I'm thinking is that if you travelled back in time, punched yourself in the face, then went back to your original time, your oldself is gonna punch his older self in the face. I agree with you on the fact that only two of you can interact at one given time (unless of course you grabbed your oldself and pulled him back in time with you) and that one loop closes once you go to the future, but your older-olderself is gonna do the same thing and so on. Therefore there would be an infinite number of loops....

    this stuff is really bakin' my noodle.
    My bad I guess I didn't see that.
  21. Mar 27, 2003 #20
    Ya know, this has all been discussed in the "Why we can't go back" thread.
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