My question is based around the popular thought experiment regarding Einstein's relativity of simultaneity. That is, the one regarding two lightning strikes and two observers. Observer 1 is stationary relative to the ground, and is located equidistant between lightning strikes A and B. Observer 2 is moving on a train parallel to the lightning strikes and observer 1. It is said that observer 2 will judge the lighting strikes to happen at different times, and observer 1 will say they happen at the same time. This is true. But often times the explanation goes beyond addressing that the perceptions will indeed view the lighting strikes as happening at different times and claim that the lighting actually happens at different times. If you had a sensor under lighting strikes A and B, could you not prove that they do happen at the same time? The perceptions are different, but the events themselves can be proven as to their time. Maybe I just don't fully understand the interpretations people give regarding it. Thanks.