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    I havent a clue in the science behind time travel and Im divided upon whether it exists. The past is history, the present is how me make of it and the future is unpredictable. Even if time travel existed, Im sure there must be another one of us making a different decision because theres billions and billions of paths we can take in our lives. If there isnt another us out there, and if we cannot travel back or forward, then it seems like the road for us is just straight. Im sure it feels better to believe you chose something instead of it being predetermined.

    I think that if time travel did exist, we wouldnt be able to change time. If we went back to try change something, something would stop us whether it be an event or just the change in decision. Maybe time travel does exist but those who travel back and forwards were already predetermined, so only to believe time travel exists only for them to be part of the process of a one way route in life.

    Also the issue of aging or living. Would we continue to age if were traveled in the past or future. Maybe if we time traveled, we would skip everything and be who we were or were going to be, but we have forgotten whats been done. Maybe we would replace ourselves mind only to have the knowledge we had when we left and nothing else. Its confusing!

    Ever heard of "John Titor"? lol, google him and you will find quite interesting stuff on him. whether hes real or not, there is something to learn. a genius hoaxer or the truth. who knows?
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    from what i understand that if you travelled at the speed of light you'd slow time down compared to whether you were stuck on Earth, which is what i understand by time travel... i'm sure some of the physics guys will explain it a bit better (just don't say nth dimentional space, 11th dimention or string theory please... it'll save my sanity! lol)

    i don't see that it's actually possible to reverse time
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    (Original post by Revenged)
    from what i understand that if you travelled at the speed of light you'd slow time down compared to whether you were stuck on Earth, which is what i understand by time travel... i'm sure some of the physics guys will explain it a bit better (just don't say nth dimentional space, 11th dimention or string theory please... it'll save my sanity! lol)

    i don't see that it's actually possible to reverse time
    well you can't travel at the speed of light, but as you approach the speed of light then time dilation would occur, I don't think this is the same as going to events in the past or future though.
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    I don't think time travel is possible. I think of the time travel paradoxes as the main reason its not possible.

    Here's one, the grandfather paradox: you go back in time and kill your own grandfather- what happens to you? If you just killed him it means he can't have had your father/mother and hence you wouldn't have been born.
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    (Original post by CJ Makani)
    I don't think time travel is possible. I think of the time travel paradoxes as the main reason its not possible.

    Here's one, the grandfather paradox: you go back in time and kill your own grandfather- what happens to you? If you just killed him it means he can't have had your father/mother and hence you wouldn't have been born.
    If you hadnt been born then you could never go back in time to kill him, hence he would be alive, hence you would be alive...woo my head hurts.

    Time travel is not possible, unless perhaps you can go faster than the speed of light, which is not possible. You cannot travel at the speed of light either. As you approach the speed of light, time dilation occurs as is shown by the Lorentz Transformations, and at the speed of light, it would effectively stop for you compared to a stationary inertial frame (of course in your frame you wouldn't notice any difference). Basically it would allow you to travel forwards through time, as you would age slower than the rest of the Earth, but you could never travel backwards.
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    (Original post by Revenged)
    from what i understand that if you travelled at the speed of light you'd slow time down compared to whether you were stuck on Earth, which is what i understand by time travel... i'm sure some of the physics guys will explain it a bit better (just don't say nth dimentional space, 11th dimention or string theory please... it'll save my sanity! lol)

    i don't see that it's actually possible to reverse time
    a friend of mine who is an imperial lecturer said 2 years ago that they had found 34 dimensions....
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    (Original post by Channy)
    I havent a clue in the science behind time travel and Im divided upon whether it exists. The past is history, the present is how me make of it and the future is unpredictable. Even if time travel existed, Im sure there must be another one of us making a different decision because theres billions and billions of paths we can take in our lives. If there isnt another us out there, and if we cannot travel back or forward, then it seems like the road for us is just straight. Im sure it feels better to believe you chose something instead of it being predetermined.

    I think that if time travel did exist, we wouldnt be able to change time. If we went back to try change something, something would stop us whether it be an event or just the change in decision. Maybe time travel does exist but those who travel back and forwards were already predetermined, so only to believe time travel exists only for them to be part of the process of a one way route in life.

    Also the issue of aging or living. Would we continue to age if were traveled in the past or future. Maybe if we time traveled, we would skip everything and be who we were or were going to be, but we have forgotten whats been done. Maybe we would replace ourselves mind only to have the knowledge we had when we left and nothing else. Its confusing!

    Ever heard of "John Titor"? lol, google him and you will find quite interesting stuff on him. whether hes real or not, there is something to learn. a genius hoaxer or the truth. who knows?
    Travelling forward in time is possible, all one needs to do is either stay in the event horizon of a black hole or just travel close to the speed of light. Although nothing as glamourous as you might find in science fiction, it would mean that you could travel to a future that you would be unable to see otherwise.
    Of course, there is the slight problem of having no facility to travel back in time again once you had finished in the future, so you would be stuck where ever you travelled to. In theory, if you travelled faster than the speed of light (impossible with the existing knowledge of physics since it is impossible to reach the speed of light, let alone pass it) you would be able to go back in time.
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    (Original post by juueru_chou)
    Travelling forward in time is possible
    Of course - we're travelling forwards in time at a rate of 1 second per second.
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    (Original post by endeavour)
    Of course - we're travelling forwards in time at a rate of 1 second per second.
    I meant travelling forward in time at an accelerated manner.

    I have just actually thought of a way to actually travel back in time which would in theory be possible, all be it technically unachievable at present.
    Since time is the 4th dimension, if one were able to enter the 5th dimension it would be possible to navigate time without having to view it in a linear way (as we do now).
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    gosh i love these kinda discussions, they make you really think and give me goosebumps.

    i know that traveling forward in time is possible (experiments on a plane travling very fast slow time time within the plane), whereas travelling back is another issue.

    I can remember two years ago in the newspaper, there was a serious article about the guy, Ronald Mallett (google his name) who said he had invented a time machine. he claimed "I am not a nut" - havnt heard from his though (maybe he's vanished in time ...)

    i would like to believe in real time travel, but somehow find it difficult to put my mind to it.

    also, aparently at the edges of the universe, galaxies are accelerating faster than the speed of light ...
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    (Original post by magicgate)
    gosh i love these kinda discussions, they make you really think and give me goosebumps.

    i know that traveling forward in time is possible (experiments on a plane travling very fast slow time time within the plane), whereas travelling back is another issue.

    I can remember two years ago in the newspaper, there was a serious article about the guy, Ronald Mallett (google his name) who said he had invented a time machine. he claimed "I am not a nut" - havnt heard from his though (maybe he's vanished in time ...)

    i would like to believe in real time travel, but somehow find it difficult to put my mind to it.

    also, aparently at the edges of the universe, galaxies are accelerating faster than the speed of light ...
    Under present physics understanding those galaxies must have no mass.
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    (Original post by juueru_chou)
    Under present physics understanding those galaxies must have no mass.
    ... :eek:
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    (Original post by homoterror)
    well you can't travel at the speed of light
    Who says?
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    (Original post by NDGAARONDI)
    Who says?
    Doesn't Einstein's famous e = mc² equation answer this?

    For instance even if you weighed only a single kilogram you would need ~8.98 × 1016 Joules of energy. A hell of a lot, and that is for something that has mass of only 1 kg!
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    (Original post by juueru_chou)
    Travelling forward in time is possible, all one needs to do is either stay in the event horizon of a black hole or just travel close to the speed of light. Although nothing as glamourous as you might find in science fiction, it would mean that you could travel to a future that you would be unable to see otherwise.
    Of course, there is the slight problem of having no facility to travel back in time again once you had finished in the future, so you would be stuck where ever you travelled to. In theory, if you travelled faster than the speed of light (impossible with the existing knowledge of physics since it is impossible to reach the speed of light, let alone pass it) you would be able to go back in time.
    I heard you could go back in time by travelling at the speed of light with a anti-gravitational field through a black hole. black holes do have something to do with time since time slows down the closer you get to it.
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    (Original post by juueru_chou)
    Under present physics understanding those galaxies must have no mass.
    Or a pretty messed up mass. If m=m_0 \gamma = m_0 \frac{1}{\sqrt{1-v^2/c^2}} and v>c (where c=speed of light) then,  m=m_0 \times \frac{1}{\sqrt{negative \ number}}

    i.e. m=WTF

    but it depends on what's meant by
    galaxies are accelerating faster than the speed of light ...
    -does that mean they're accelerating greater than 3*108 m/s²; or that they're accelerating to a speed greater than 3*108 m/s?
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    Einstein suggests that the distinction between the past, present and the future is only an illusion. Things do not become, they have not been and they will not be, they simply ARE. Time is like space.
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    (Original post by CJ Makani)
    Doesn't Einstein's famous e = mc² equation answer this?

    For instance even if you weighed only a single kilogram you would need ~8.98 × 1016 Joules of energy. A hell of a lot, and that is for something that has mass of only 1 kg!
    Einstein did say you cannot travel faster than the speed of light in a vacuum. We don't really know what space is given all this dark matter and stuff we don't know about.
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    (Original post by CJ Makani)
    Doesn't Einstein's famous e = mc² equation answer this?

    For instance even if you weighed only a single kilogram you would need ~8.98 × 1016 Joules of energy. A hell of a lot, and that is for something that has mass of only 1 kg!
    The problem is not the energy required, it is more of the faster you go, the heavier you get so very near the speed of light your mass will be very great already and would keep increasing to infinity. this would mean that the energy needed would increase exponentially. In order to travel faster than the speed of light [in a vacuum] you would need zero mass.
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    (Original post by juueru_chou)
    The problem is not the energy required, it is more of the faster you go, the heavier you get so very near the speed of light your mass will be very great already and would keep increasing to infinity. this would mean that the energy needed would increase exponentially. In order to travel faster than the speed of light [in a vacuum] you would need zero mass.
    And the force to get you that fast will be too big according to F = ma. But then who says that equation works when v = 0.98c etc?
 
 
 

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