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Expanding universe and light

  1. Oct 7, 2015 #1


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    As the universe expands, space itself gets "stretched" and objects drift apart, like dots on elastic surfaces when force is applied. So one meter billions of years ago is two meters today, but does it necessarily mean light takes twice as long to travel this "new meter"?
  2. jcsd
  3. Oct 7, 2015 #2


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  4. Oct 14, 2015 #3
    This is kind of similar to a question I have.
    My question is: do we know that time stays consistant throughout all the universe. We know that time and space are intertwined, and that time is relative depending on mass, such as near an event horizon. Does the absence of any mass, out in the voids of space, between galaxies, also affect time's consistancy? If not, would light pass though these areas at a different rate comparatively?
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