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Speed of light and Time Travel

  1. Mar 3, 2004 #1
    Well, We all know about Einstein Theory of Relativity.

    The speed of light is constant.
    And if someone travels close to the speed of light; time goes slower than someone walking on earth etc.

    Ok, this is my question. (Involves Pilots)

    Ok, since pilots travel at amazing speeds of 1,000 - 3,000 miles or higher in Military Jet planes and commercial planes and they experience 3-6 times the G force of earth. Let's say a pilot is flying around the world for 24 Hours straight let's assume.

    So, in those 24 hours traveling at those fast speeds. Does the pilot age a bit slower than normal human aging during that 24 hour period?

    Explain.
     
  2. jcsd
  3. Mar 3, 2004 #2
    I believe that the answer is yes, but only very very very very very very slightly. I mean, how does 3000 compare to 300000000? And then, in many cases, 90000000000000000? Not much at all.
     
  4. Mar 3, 2004 #3
    The pilots i seen so young and they are very old.


    Specially this 79 year old men looking like in his 40's year old.

    But, the others around 50's


    He must of pulled a lot of G's in his flights. ;)

    hehe.
     
  5. Mar 3, 2004 #4
    *smacks forehead*

    [tex]
    t = \tau\gamma
    [/tex]

    [tex]
    \gamma = \frac{1}{\sqrt{1-\frac{v^2}{c^2}}}
    [/tex]

    [tex]

    v = 14432 \frac{meters}{sec}
    [/tex]

    [tex]

    t = \frac{\tau}{\sqrt{1-\frac{14432^2}{299792456^2}}}
    = \frac{\tau}{\sqrt{1-2.317x10^{-9}}}
    [/tex]

    [tex]

    = \frac{\tau}{0.99999999884127}
    = 1.0000000011587\tau
    [/tex]

    given that the g forces are only experienced during acceleration and never exceed ten gs (for medical reasons) we can calculate:

    [tex]
    ds^2 = 1-\frac{\frac{2GM}{c^2}}{R}dt^2
    [/tex]

    [tex]
    ds = \sqrt{1-\frac{8.86112x10^{-3}}{6x10^24}}dt
    [/tex]

    [tex]
    ds = \sqrt{1-1.47685x10^{-27}}dt
    [/tex]

    that is for 1 g, which the coefficient is obviously insinificant. If we make the earth ten times more massive(10 g basically) we get:

    [tex]
    ds^2 = 1-\frac{\frac{2GM}{c^2}}{R}dt^2
    [/tex]

    [tex]
    ds = \sqrt{1-\frac{8.86112x10^{-2}}{6x10^24}}dt
    [/tex]

    [tex]
    ds = \sqrt{1-1.47685x10^{-26}}dt
    [/tex]

    Which remains insignificant. Any added g forces will have essentially nil effect, the special relativisitc effects of the high velocity however are measurable by atomic clocks, but not significant in terms of a human lifetime or any amount of time recognizable by humans. For example if you lived a hundred years by your watch at that velocity some remote observer would measure 100.00000011587 years, which amounts to a net difference of 3 seconds over 100 years. Not much.
     
    Last edited: Mar 3, 2004
  6. Mar 3, 2004 #5

    HEY franznietzsche!

    I did not typed that second post.

    I was away from the computer and my little immature brother sat down and post that.. i think he deleted some of my files..

    kids.. bah...
     
  7. Mar 3, 2004 #6
    meh, either way, was good excersize for me.

    But yeah the pilot does age more slowly, just not much. Its very insignificant as the numers show.
     
  8. Mar 4, 2004 #7

    HallsofIvy

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    Hey! I'm going to use that the next time I suddenly realize that I had just said something stupid!
     
  9. Mar 4, 2004 #8

    ZapperZ

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    Hehe... GREAT idea! I'll use that too, except I'll blame it on my evil twin Skippy! :)

    Zz.
     
  10. Mar 4, 2004 #9
    hmm..


    HallsofENVY you think you're some kind of physic?


    Ook , ms cleooo^^^
     
  11. Mar 4, 2004 #10
    Damn. So, one would have to travel at a velocity 10.5 million times that of a jet for 100 years to "gain" a single year due to time dilation? That's if I even have my math right.
    In any event, I can see that we don't fly jets for longevity.
     
  12. Jul 8, 2010 #11
    From Franz's post above - am I right in thinking that the centrapeital force experienced from loop de looping in a plane (or in any other way) contributes towards time dilation in the same fashion as being in a gravitational field?

    Because I've never heard that before (my knowledge of special relativity is reasonable and of general, minimal.)
     
  13. Sep 7, 2010 #12
    Sir
    if we travel around earth in opposite motion for 20 yrs then could we can go to past
     
  14. Sep 7, 2010 #13

    HallsofIvy

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    A very strange assertion. Do you have any evidence to support it?
     
  15. Sep 7, 2010 #14

    Vanadium 50

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    I think that was part of the plot of one of the Superman movies.
     
  16. Sep 8, 2010 #15

    Doc Al

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    No. You'll still be going into 'the future', regardless of your direction of travel.
     
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