Consider the two events R and Q in Fig. 5.21. According to S, the event R takes place before the event Q, because R lies on an earlier simultaneous space than Q; but according to M, it is the other way around, Q lying on an earlier simultaneous space than R. Thus, to one observer, the event R takes place before Q, but for the other, it is Q that takes place before R! (This can only happen because R and Q are what are called spatially separated, which means that each lies outside the other’s light cone, so that no material particle or photon can travel from one event to the other.) Even with
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Re read whole section.
Time is contingent on light cones, meaning time is not universal and materials inside the light cone of two events would experience time differently. If two objects are movijng towards me I will see the object closest to me 1st, followed by the second object. However, if there was an observer behind said objects facing me he would see the second object (relative to me) first and the first object (relative to me) second.
think of two baseballs being thrown at me to visualise this concept.
