This discussion centers on a relativity problem involving a train and a platform, specifically addressing the paradox of length contraction and simultaneity. The train, measuring 100 meters, approaches a 1-kilometer platform at high velocity, leading to differing observations from the train's and platform's reference frames. Observers on the platform see the train as a short 10-meter object that never fully passes the platform, while passengers in the train perceive the platform as short and believe they have passed it. The conversation highlights the relativity of simultaneity, where events that are simultaneous in one frame are not in another, leading to the conclusion that the front of the train does indeed pass the platform in all frames, despite the apparent contradictions.
PREREQUISITESStudents and enthusiasts of physics, particularly those interested in special relativity, as well as educators seeking to explain complex concepts of time and space in a relatable manner.
I am not sure anymore what you are sayingFarsight said:
If the train does not remain rigid, then the train can elongate, and it definitely will if each part accelerates instantaneously. And if you add something like the Born rigidity condition, the train must accelerate over an extended period, so even if the middle of the train begins to accelerate at the moment it passes the middle of the platform, it may not stop until it has passed the end of the platform.Farsight said: