The train in a tunnel paradox / ladder paradox visualized

Also known as the ladder paradox, the train in a tunnel paradox challenges one’s understanding of length contraction in Einstein’s Theory of Special Relativity. A long futuristic train goes through a shorter tunnel and is seen from the perspective of a trainspotter on the ground and from the perspective of a passenger on the train. The two accounts of what happens are wildly different, but they are consistent. This video was born as an experiment of matching content to a soundtrack. I am also working on a relativistic video game that aims to make Special Relativity more intuitive and less paradoxical. I believe that human intuition can crack relativity if given a chance. You can follow me at and support me at #physics #space #time #relativity #paradox === Technical details === The train is simulated as a Born-rigid body. Each vertex in its 3x3 mesh follow a piece-wise hyperbolic trajectory. The vid