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Tachyons and Time

  1. Aug 13, 2005 #1
    1]Tachyons are substances that travel faster than light.
    2]The speed of light is approximately 3,00,000km/s (1,86,000mi/s)
    3]Tardyons are particles that travel at speeds lower than light
    4]With increse in speed time slows down.
    5]Time travel at the speed of light. (from 4)

    ***My Question is***
    Since, time travels at speed of light and tachyons travel faster than light, tachyons travel faster than time. Does that mean that tachyons are emitted before and event occurs. If it does, then it means that all things were planned out before the formation of the universe. This thing is puzzling me :confused: :confused: :confused: :confused: :confused: :confused:
  2. jcsd
  3. Aug 13, 2005 #2


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    I am dubious of your logic, particularly steps 4 and 5.

    However, yes, I believe that tachyons do travel backward in time.

    You don't have to worry about time travel though, since they cannot cross the light barrier, they cannot interact with anything moving forward in time, thus no paradox.
    Last edited: Aug 13, 2005
  4. Aug 13, 2005 #3
    But their existence is speculative though, since none have been observed.
  5. Aug 13, 2005 #4


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    fixed a few things
  6. Aug 13, 2005 #5


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    Is there a reason why you are being this confused and worrying about something that is so far only a mathematical ARTIFACT? I can give you plenty of other things to twist your mind on AND, have been verified to exist.

  7. Aug 13, 2005 #6


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    [4] is correct for tardyons, and incorrect for tachyons.
    [5] is very confused - I suppose you mean that time dilation goes to infinity as velocity approaches 'c'.

    The time dilation factor 'gamma' for tachyons turns out to be imaginary (I'm not sure how to physically interpret this statement).

    gamma = 1 / sqrt(1-(v/c)^2)

    Note that |gamma| decreases as v increases for tachyons (that's why [4] is wrong).

    You might also be interested in the sci.physics.faq about tachyons


    which makes the bizarre point that while tachyons travel faster than light, they do not necessarily enable one to send information faster than light.
  8. Aug 13, 2005 #7
    at FTL, time is imaginary, not negative
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