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Summary
DescriptionGalilean Spacetime and composition of velocities.svg
English: In Newton's theory, time is universal, not the velocity of light. The Galilean transformations are t' = t and x' =x - vt. Galilean addition of velocities is illustrated by the following thought experiment: The red arrow illustrates a high speed train traveling at 0.4 c. Within the train, a passenger runs towards the front of the train at a speed of 0.4 c. The sum of their velocities is represented by the blue arrow, 0.8 c. This is in accordance with our naive expectations.
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