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B How do we know the stars are not our own light falling back.

  1. Mar 27, 2017 #1
    How do we know that the stars we see, or some of them are not the light from our own system falling back, and that we may be looking at light from our own star/solar system/ galaxy that has taken millions of years to fall back on its point of origin?
     
  2. jcsd
  3. Mar 27, 2017 #2

    phinds

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    Gold Member
    2016 Award

    Why do you think it is possible for light to "fall back"? How would this result in our seeing MILLIONS of distinct galaxies? How would it account for the specific red shifts of distant galaxies? I could go on and on but it's pointless. The answers are many-fold.
     
  4. Mar 27, 2017 #3
    We could be falling through a universe rather than moving "up and out" through it, the shell of this universe could be collapsing and the reflected points are where light is reflected from, our could be a focal point due to lensing. Light, which is also a particle, and can not escape a black hole, would first rise "up" from our point, (constantly moving) and eventually get drawn back in the same direction we are headed
     
  5. Mar 27, 2017 #4
    Of course this is probably not the case, but for the interest of the point of view, at x magnitude of gravity, in a fixed point how far could a photon travel before being bent back to its point of origin. Perhaps also to not think of it like a ball going up and down, gravity could bend that light around in a circle, so even if the point of origin moved through space, the gravity could be bending light back around and in the direction of our observation point, so would appear to be ahead of us in the direction we are travelling through the universe.. Also to explain the millions of point sources (stars and galaxies).. the light would only come back as a diffuse glow if a reflective boundary was uniform, if there was a boundary to the universal bubble that was pointed like a tesseract, the observation would be different, with light being focused at points.
     
  6. Mar 27, 2017 #5

    fresh_42

    Staff: Mentor

    Yes, and my first thought has been the line spectra of the stars we observe, or the radio emissions, or gamma emissions or, or, or. As @phinds has said: the answers are many-fold.

    There is simply no way that the electromagnetic waves we receive are originated by ourselves.

    The question has been answered and a further discussion makes no sense.
    Thread closed.
     
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