Spacetime diagram

Graph of space and time in special relativity

A spacetime diagram is a graphical illustration of locations in space at various times, especially in the special theory of relativity. Spacetime diagrams can show the geometry underlying phenomena such as time dilation and length contraction without the need of mathematical equations. The history of an object's location through time traces out a line or curve on a spacetime diagram, referred to as the object's world line.

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