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Frames of Reference Question

  1. Jan 29, 2007 #1
    Suppose event A causes event B. To one observer, event A comes before event B. Is it possible that in another frame of reference event B could come before event A? If so, how?
  2. jcsd
  3. Jan 29, 2007 #2
    What is the special invariant quantity in special relativity?

    Given two events, A and B, how does one define an invariant distance between them?

    If you can calculate this special distance in one frame, what is its value in any other inertial frame?

    What does this tell you about the "ordering" of events?
  4. Jan 29, 2007 #3


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    This implies that B is in the interior of, or on the boundary of, the future light cone of A.

    The only information that this adds is that B isn't on the boundary of the future light cone of A, so it must be in the interior.

    No. If B had been outside of the future light cone of A, it would have been a different story. I suggest that you draw space-time diagrams to see why this is so.
  5. Jan 29, 2007 #4
    awsome, thanks guys.
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