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I Objects that move faster than Speed of light

  1. Aug 27, 2016 #1
    Are objects beyond the observable universe in some sense moving faster the the speed of light. Given that objects at the edge of the observable universe are "maximally" red shifted, objects beyond that theoretically must be more red shifted, which is impossible. Is it therefore a nonsense to believe that anything exists beyond 13.8 billions light years away? I understand the answer is no, but I thought it an interesting topic.
  2. jcsd
  3. Aug 27, 2016 #2


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  4. Aug 27, 2016 #3


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    Only in a coordinate dependent sense which has no physical relevance. If you want to be rigorous, there is no way of saying that two objects are moving with a particular relative speed unless they are at the same place (or sufficiently close so that spacetime can be considered locally flat).

    This is a logical fallacy. It only means that the light from those objects will never reach you - which is the same statement that you started with.
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