The speed of light may have been broken.

Discussion in 'Physics & Math' started by Pincho Paxton, Sep 22, 2011.

  1. wlminex Banned Banned

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    neutrinos subjected to acceleration close to c would experience L-F contraction . . . distance would (relatively) be shortened . . . . appearing (to observers/detector) to have arrived earlier than anticipated. It's a good thing the neutrinos weren't really accelerated to >c (NOT!) . . .as they would have arrived before they left!
     
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  3. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    The bar for genuine scientific research has never been higher at sciforums.
    Now even the results of experiments at Cern are dumped into Pseudoscience.
     
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  5. Emil Valued Senior Member

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    LOL....something like Relativity of simultaneity?
     
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  7. OnlyMe Valued Senior Member

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    I think I covered that in my post, but...
    When did they build the vacuum tube 500 miles long and straight through from end to end? Like I attempted to say the best I could figure is a fiber optic line running the 500 miles and that in itself is a hard one. Even so the refractive index of the finer would vary with temperature etc. And how could they measure the length accurately?

    That was a joke! And the Murdock reference had to do with the cell phone hacking issue his papers are facing in the UK and perhaps even US. You know reliable sources...
     
  8. Pincho Paxton Banned Banned

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    Relativity, and The Big Bang Theory coming soon to a thread near you!

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  9. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

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    Yeah, I wonder how much the distance is shortened for light travelling at c?
    The neutrinos didn't so much arrive "earlier than expected" but earlier than light would have done.
     
  10. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

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    Ah. I was thinking more of the fact that Murdoch owns The Sun and the News of the World. Both famed more for lurid sensationalism than accuracy.
    On the other hand I should have known it wasn't from a Murdoch-owned paper because there was no mention of naked boobs in the article.

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  11. OnlyMe Valued Senior Member

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    That's probably the answer right there. Since neutrinos have mass there would be some length contraction involved. The neutrino traveling even close to c would have to travel a shorter distance than a photon. Since a photon has no mass it experiences no length contraction...

    (another attempt at humor. Length contraction cannot be applied to distances.)
     
  12. Emil Valued Senior Member

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    Yes, in some way ...
    You did forget the technology used in laser rangefinder?
     
  13. Emil Valued Senior Member

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    Agreed mentioning that cannot also apply to the length.
     
  14. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

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    Huh?
    What is length if it's not a distance?
     
  15. OnlyMe Valued Senior Member

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    Emil, we are talking timing, the time it takes a neutrino to travel 500 miles through the earth in a straight line, in one direction only. There is no equivalent line of sight for a photon to travel as they cannot make it through 500 miles of dirt or rock or whatever.

    The synchronization required is that the detector 500 miles away must know when the neutrino left its point of origin and the exact distance between the two locations.

    Any path that light can take between the two must by necessity be longer than the path the neutrino takes. And both must be known to within 60 nano seconds of light time. If light is used as a standard.

    I raised the issue of fiber optics because if a fiber optic cable were used for the light path not only would its length need to be known "accurately", the refractive index of the fiber would also have to be know over its entire length. Even a change in temperature in the fiber would have an affect on its refractive index and thus the light travel time through the fiber.
     
  16. OnlyMe Valued Senior Member

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    Length contraction in this situation applies to the length of an object that is in motion. It does not apply to any distance the object travels while in motion.

    The distance traveled was not itself in motion so it cannot become length contracted.

    A neutrino itself can become length contracted but the distance it travels cannot.
     
  17. Dywyddyr Penguinaciously duckalicious. Valued Senior Member

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    If an object is moving at relativistic speeds then to it the universe is doing so while the ship itself can consider itself stationary. Distances become shortened. This is why a ship at relativistic speeds takes "less time" to reach its destination - because it's effectively not travelling as far.

    Or at least that's what I remember.
    Where's the error?
     
  18. OnlyMe Valued Senior Member

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    That is really the nut of the twin paradox. It presents a picture that cannot be reconciled. With time dilation you can bring two clocks back together and compare elapsed time. With length contraction the same does not happen.

    But this is a whole different subject and is confused enough that it is still debated today though it is now more than 100 years old.

    Once someone answers all known twin paradoxes, someone Else will present yet a few more.
     
  19. chinglu Valued Senior Member

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    Simple, the neutrino is not doing the measurement. So, who cares what it thinks.

    The stationary earth observers are doing the measurement.
     
  20. RedRabbit Registered Senior Member

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    This might be a stupid question...physics isn't my strong suit...but how would they know when the neutrino had started it's journey?

    I presume they have a way of measuring the exact moment that the light begins it's journey, but where does the neutrino come from? Do they create it and do they know exactly when they've created it?

    Told you it was stupid.
     
  21. Emil Valued Senior Member

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    Demonstration of length contraction is based on distance contraction.
    Read this.
     
  22. OnlyMe Valued Senior Member

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    The neutrinos are created. This is done in a way that the direction it will travel is also known. Once created we know of no way to chage its direction or velocity.
     
  23. chinglu Valued Senior Member

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    Uh, in the rest frame, everything is Euclidian.

    If a material point is at rest relatively to this system of co-ordinates, its
    position can be defined relatively thereto by the employment of rigid standards of measurement and the methods of Euclidean geometry, and can be expressed in Cartesian co-ordinates.


    http://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf
     

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