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Alternate dimensions or Universes

  1. Jul 26, 2003 #1
    I'm wondering what is thought or say parrallel or alternate uviverses and dimensions. What would be possible, or better yet, what wouldn't? When i usually consider anything about existince or reality or anything like that (philisophically or theoretically anyways) i always consider the possibilty that this isn't the only reality that exists. I often even forget that most people would assume this was the only real reality.

    Also, do you think it's possible to enter an other universe or dimension? and... if the universe is infinite how would that effect the possibilty of other universes? how would the expanding effect other universes. and... do other universes or dimensions exist in what we would consider the same "space" as our world???
  2. jcsd
  3. Jul 29, 2003 #2


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    I was watching something, I think on Discovery, that said something about probabilities. Basically, it said that more then likely, at some x distance away from here, there is another me, responding to another you, in a similar manner.

    Then theres the idea that every decision branches off into other possible dimensions. For instance, there is a universe where I did not respond, and this one where I did.

    All this stuff is cool to think about, but hard to understand, IMO.
  4. Jul 29, 2003 #3


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    Well, be sure not to confuse alternate universes with an extra dimension, as they mean quite different things. The concept of an alternate universe, as in the many worlds interpretation of QM is hard to imagine. In such a case, the idea is that everything that is logically possible (given a number of initial assumptions) is real. This doesn't matter whether or not the universe is infinite, since all these possible/real world are contained within the same wave function.

    Of course, in the ontological sense, that wave function is still part of the same single universe (all that exists) and so a true multiverse is a logical impossibility.
  5. Jul 29, 2003 #4
    There is a theory related to time travel that there are many very similar universes that differentiate by a small degree, one on top of the other. So say time travel were possible, then if you theoretically went back in time and kill your grandfather it would be a paradox because if you do that, you were never born, in which case you never could have travelled back in time. Well one theory is that instead of a paradox, it would create a completely seperate timeline (or alternate reality, universe, etc). So in one you would have lived to travel back in time to kill your own grandfather, and in the other you never were born because your grandfather never had your father, who in turn never had you. I believe Hawking talks about this in one of his books, but I know it's an older popular theory not originating from him.

    Also see M-theory, or superstring theory in which it's proposed that there are in fact 10 dimensions which are actually curled up and away from our universe. It's difficult to visualize, so rather than fumble through it, I'd suggest looking it up on the net, or maybe someone else can better articulate it than me.

    As far as the universes "colliding" or something- basically the they would exist in the same space as our current universe, in a different plane, or "phase" of existence. Travelling between those dimensions?

    See star trek
  6. Jul 29, 2003 #5


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    I believe that Hawking (others possibly too) have talked about time traveling back and causing some event that REINFORCES the fact that you traveled back. It is a closed loop. I think it was visualized by a billiard ball on a pool table getting knocked around by another ball or some such thing. I believe I saw it on NOVA. An example would be similar to what happens in the movie Terminator. Suppose you go back in time to kill an enemies parent. You don't succeed. You have to know going back that you don't succeed because if you had succeeded there would be no reason to go back. It will never happen. It seems like a Laurel and Hardy show when you think about it but it is actually quite opposite. When you watch Laurel and Hardy every possible thing that could go wrong does. The same thing would happen with time travel. You go back in time and your car breaks down and you miss your oppurtunity, or you get in an accident, or you miss when you shoot, or any number of possible things. But they HAVE TO HAPPEN because if you suceed there was no point in going back. So when it seems like a cruel joke played on you by the fabric of the universe, it is really not. All of the possible sucesses have been eliminated because obviously you have a reason to travel in the first place. It is almost as if the universe has fate built right in.

    Now, suppose we don't buy into this closed loop BS. Travel back, kill your enemy, timeline changes, never had a reason to go back, so on and so forth. Would we know the difference? Do we remember things that didn't happen? This is why I have suggested that it is possible we time travel all the time and just don't realize it.
  7. Jul 29, 2003 #6

    Right, I may have been wrong on hawking being the one who said it. but my theory(meaning the one i'm explaing now, not the one I made;) is known as the split timeline theory, whereby each time events in time are changed, it creates a seperate timeline, or reality in which events contrinue along a different path. In one reality the person you killed is dead, in the other he's not because you never went back in time. I'll see if I can find some info on it.
  8. Jul 30, 2003 #7


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    There was a movie that I’ve watched but I couldn’t remember the name. The movie presented the concept of the looping theory very clearly that I understood straight away (even though, by then, I couldn’t understand English well). I think it was Bruce Wallace. When he was a little kid he saw a man killed in front of him in the airport. When he grew up, there was a virus outbreak that wiped out most of the population. He traveled back in time and tried to stop the man carrying the virus. His pursue took him back to the airport he has been when he was a little child and there he was shot. Before he died, he saw a little boy staring at him and only then he realized that the little boy was he himself. I didn’t like the movie because it hadn’t a happy ending but I understood the message that the event can not be changed but changing the event is also apart of the event that is happening.
    Now let’s talk about split time line theory. If I go back in time my own time line will divide like the flow of blood vessels, but it’s hard to imagine because that means that realities (each with their own time lines) are infinite and the possibilities are infinite. So I imagine that by going back in time and changing things, you’re not actually changing the event since you can never see out come of the event. You are just creating another reality of your own.
  9. Jul 30, 2003 #8
    The movie is 12 monkeys, bruce willis- excellent film.

    Anyhow, you're correct, the permutations would be infinite based on uncommon events such as time travel, which is why if there were time travel, it would be strictly monitored and policed. Divergent timelines would create an entire duplicate reality where everything was identical up to the point of divergence, but after that, a ripple effect would ensue, change an infinite number of things through cause and effect. It's like the story of the man going back in time and picking up a single rock in the prehistoric erea, only to arrive back home and find everything completely foreign to him. Even the smallest change could have enormous implications. It's not just something that was made up for "back to the future" It would indeed change an infinite number of things.
  10. Jan 15, 2004 #9
    alternate demensions

    i remeber a laser based test that proved that alternate demensions existed the i think it was two laser reflected 4 r 5 times the same way and looking at the differances i could be completly wrong but thats what i think it was and that it was acutaly theorised by a person along time ago b4 lasers were invented he had done it some how with something Lol but i cant seem to find it antwere if anyone knows what im talking about plz eamail me ar xxdominationx@aol.com r post ill check back in awile

    P.S. if time travle exist r will ever can effect proced cause r we already effected ?
  11. May 26, 2004 #10
    I belive this is based upon the theory of quant mechanics. Imaging you're tossing a coin. For every possible event a new universe is created. Kinda weird.

    BTW I've heard a new theory, dark materia is gravitrons from another universe.
    Last edited: May 26, 2004
  12. Aug 20, 2004 #11
    I always liked the idea that there was an alternate universe for every possible action that could have occured in this universe.


    This morning I speed up to run a yellow light on the way to the mall. At the mall I run into a friend I have seen in years and we talk for a few minutes before he leaves.


    I get caught at the light, make it ot the mall a minute later. Dont see my friend since he left a minute before I get there. The friend gets into a car accident that he would not have been in if I had stopped to talk to him.

    Every little action has a universe based around what chocie was made.
  13. Aug 20, 2004 #12
    just a humble opinion from a mind that has played with these concepts for 30-40 years.

    as best i can sense or understand how we will ultimately visit other dimensions and altenated universes will be through a redirection of our consciousness.

    while in a meditative state we will be able to focus our consciousness on our other lives, in this and other dimensions and universes. i believe that we do this unconsciously when new information about a past event changes our feelings about that event. while sleeping or dreaming we go back in time and re-experience that event with the new information. upon awakening, our body chemistry, emotions, etc have all changed.

    we now 'remember' that event with a new history.

    i doubt that we will ever 'physically' travel into these other worlds. have you ever had a feeling that someone was whispering into your ear to make a decision or do what seemed like the opposite of what you wanted to do. Was that a future you or another of your personaility's in another world refocusing his, her consciousness and visiting or traveling back in time? to talk to you.

    ah, better than sci-fi! I think this happens everyday. we just are not trained or experienced to sense it's occurrence.

    olde drunk
    Last edited: Aug 20, 2004
  14. Aug 24, 2004 #13
    Thanks for sharing your thoughts, got me thinking a bit more - especially the dream thing. Some dreams seem too real to just be dreams, when you go to sleep, you wake up in other dimension and when you go to sleep there, you wake up here. You just can't remember it, well only fragments of it?
  15. Sep 10, 2004 #14
    if there are infinite dimensions then why can't a version of our selfs or an intirly difrent species of people with higher technology Physically come to our dimension
    or it may be intirly impossible i know i may be answering my own question but it could be some kind of paradox since there are infinte dimensions then the travelers would turn up in a world like ours but it wouldnt be the same or maybe our dimension changes but i love the theory that every action splits into multiple dimensions it trills me to think about the possibilitys of the universe if only i see other lands other hopes change mistakes mend wounds
    but please if im wrong please dont make fun of me im only 15
    Last edited: Sep 10, 2004
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