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The mystery of the creeping ray and relativity.

  1. Mar 26, 2013 #1
    I have been doing many experiments with light and magnetism,

    and one of the things I noticed is that when light is passed on the right side of a sphere (e.g.) some of the laser rays will deflect from a straight path and bent towards the left. I believe this is known as the "creeping ray".

    Can someone refer me to what causes the creeping ray or just explain it?

    Secondly; it is claimed that a famous eclipse "proved relativity" when light could be seen behind the sun because "space-time" bent light, however what if this effect is the "creeping ray" effect and not mass bending space. Can someone show me some proof that the creeping ray was taken into consideration when formulating the equation for the eclipse because i haven't seen any.

    From what I have seen it seems that the effect of light bending around the sun is given off by creeping ray effect and not by mass bending space so much (i mean this effect can be replicated with tiny masses).

    Thanks for your help and good luck with your works!
  2. jcsd
  3. Mar 26, 2013 #2


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    Diffraction is negligible for light propagation in the solar system. And even if your "creeping ray" is some surface effect or whatever, this is negligible as well.

    With current telescopes, it is possible to see the deflection of light even if you look perpendicular to the sun. It follows exactly the pattern predicted by general relativity, and it has to be taken into account to determine the proper position of the stars.
  4. Mar 26, 2013 #3


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    The creeping ray is a well-known effect in optics:
    Light deflection by a gravitational field is quite different - not diffraction, not a surface effect. It was originally observed by Eddington during a solar eclipse, in which the deflection was measured over an entire field of stars and the expected magnitude and systematic variation with distance from the sun was confirmed. Nowadays the effect is known as gravitational lensing, and you can find many dramatic illustrations of it on a galactic scale.
    Last edited: Mar 26, 2013
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