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Timelike and spacelike.

  1. Oct 31, 2007 #1
    Please,can you simply explain the meaning of terms time-like,space-like,time-like separated,space-like separated.I searched in web for an hour but all explanations are very complicated.I didn't understand anything.

    IS the time-like separated means just difference in time of two points in some frame at dx=0 at this frame?
  2. jcsd
  3. Oct 31, 2007 #2
    If two events are time-like separated, then an object can travel from the first event to the second event with a velocity v<c.

    Events separated by a time-like interval are always arranged in the same order in time. That is, if an observer O deduces that event A happens before B, then another observer O', moving relative to O, will also come to the same conclusion. There is a before and after. And there is a possibility that that event A will influence event B. (Cause and Effect.)

    In a space-like interval, an object can be present at both events only if it travels at a velocity v>c. Since no object with mass can travel at such a speed, the two events are not causally connected. Also, there is no particular order between A and B(in time) if they are space-like separated.

    On a spacetime diagram, for time-like events A and B, B will be within the light-cone of A and vice-versa. For space-like intervals, one event is outside the light-cone of the other.
  4. Oct 31, 2007 #3
    Thank you very much.It seems to that I understood something.
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