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Physics, Astronomy & Cosmology / Re: What does "time-like" mean in the following sentence?
« on: 27/10/2017 21:08:53 »
By Neutrino
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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. "
And light propagate at 'c', which is a definition made by a ruler and a clock
"
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. "
And light propagate at 'c', which is a definition made by a ruler and a clock
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