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Gravity's effect on light

  1. Oct 26, 2015 #1
    Question: If gravity can bend light toward it's source, or even hold it back so to speak (like a black hole), how does light bend around a star like photo attached? It seems if gravity pulls light toward it, the light shouldn't move out and around the star/sun but bend into it?

    DSCF7398.jpg
     
  2. jcsd
  3. Oct 26, 2015 #2

    DaveC426913

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    You are interpreting the picture wrong.

    The pic is confusing because the light ray is not aligned with the grid. But light rays can go any which way they want. This one happens to be crossing the imaginary grid at an angle.

    But rest assured: that light ray is coming directly - in a straight line - from its source.
     
    Last edited: Oct 26, 2015
  4. Oct 26, 2015 #3

    DaveC426913

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    Look what happens if we add more light rays. These rays are from a near point source, so they radiate outward from that point.
     

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  5. Oct 26, 2015 #4

    DaveC426913

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    But this might make more sense. Here, the light rays are coming from a distant source, so they are all parallel.
    They remain parallel until they enter the star's gravity well, then they bend inward.
     

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  6. Oct 26, 2015 #5
    Scratch that, now I see what your saying, your first pic shows it, their graphic (that I posted) is what threw me, yours is a better visual showing more light paths, thanks!
     
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