Can the Order of Events Change in Different Frames of Reference?

GreenLRan
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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?
 
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GreenLRan said:
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?

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?
 
GreenLRan said:
Suppose event A causes event B.
This implies that B is in the interior of, or on the boundary of, the future light cone of A.

GreenLRan said:
To one observer, event A comes before event B.
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.

GreenLRan said:
Is it possible that in another frame of reference event B could come before event A? If so, how?
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.
 
awsome, thanks guys.
 
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