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Time travel and guff of the like

  • 20-02-2008 9:06pm
    #1
    Xhristy
    Closed Accounts Posts: 510 ✭✭✭


    This post has been deleted.


Comments

  • #2
    Hellm0
    Registered Users, Registered Users 2 Posts: 1,028 ✭✭✭Hellm0


    My understanding(and I may be wrong) is that if one were to reach the speed of light you would reach infinite mass. In a nutshell you would be both the observer and the observed.


  • #3
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,757 CMod ✭✭✭✭Spear


    Xhristy wrote: »
    This post has been deleted.

    Nothing with mass can travel at c, the question is irrelevant and pointless.


  • #4
    Xhristy
    Closed Accounts Posts: 510 ✭✭✭Xhristy


    This post has been deleted.


  • #5
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,757 CMod ✭✭✭✭Spear


    Xhristy wrote: »
    This post has been deleted.

    I wasn't being a jackass and there was no need for personal abuse. There is no answer possible, theoretically or not. If you don't want a factual answer then don't ask the question.


  • #6
    Gurgle
    Closed Accounts Posts: 5,064 ✭✭✭Gurgle


    Xhristy wrote: »
    This post has been deleted.
    If you limit the detection of his location to the reflection of light off him, then even if he travelled instantaneously he would still seem to get there very soon after he left & arrived.
    Xhristy wrote: »
    He would still see light at the same speed and so would the observer but the observer would see him arrive before he left.

    Am I making sense or am I missing a majorily obvious mistake.:D
    Thanks
    Think at the limits.
    If he travelled instantaneously, arriving exactly where he was, the observer could not detect that he had moved. If he travelled slightly slower than instantaneously, there would be a 'flicker' lasting as long as he wasn't there.

    This whole notion of travelling faster than the speed of light moving you backwards in time is a paradox. Its what you get if you extend the time dilation effects of velocity beyond c, where the effect converges to 0.

    Objectively time would stand still for someone travelling at the speed of light. To accelerate beyond c would require an objectively instantaneous increase in velocity, i.e. infinite acceleration and therfore infinite energy.


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  • #7
    SOL
    Registered Users, Registered Users 2 Posts: 1,155 ✭✭✭SOL


    They have done experiments with this afaik. It can be demonstrated using tachyons I think. of course this is only in media and the speed of light in a vacuum is still constant, if I find any articles I'll try post them up, maybe try looking up tachyons in wikipedia

    http://en.wikipedia.org/wiki/Cherenkov_radiation


  • #8
    gondorff
    Closed Accounts Posts: 388 ✭✭gondorff


    Spear wrote: »
    Nothing with mass can travel at c, the question is irrelevant and pointless.

    Has the photon no mass?


  • #9
    Spear
    Moderators, Computer Games Moderators, Technology & Internet Moderators, Help & Feedback Category Moderators Posts: 25,757 CMod ✭✭✭✭Spear


    gondorff wrote: »
    Has the photon no mass?

    No, but it's energy is sometimes stated as the equivalent of it's rest mass.

    http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/photon_mass.html


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