#### Can a Theory be Proven Right?

This is based on one of the lectures of Richard Feynman (1918–1988), a theoretical physicist and Nobel Prize winner, describing the process by which theory and practical studies are used together to make scientific discoveries. In general, we look for a new law by the following process: First, we guess it. Then we compute the

#### Spacetime Diagram

The spacetime diagram (“a position vs time graph”) is a valuable tool for modeling and interpreting situations in relativity. As I like to say, “A spacetime diagram is worth a thousand words.” Many problems and “apparent-paradoxes” (or better “puzzles”) can be resolved by drawing a good spacetime diagram. However, because Minkowski spacetime geometry is not Euclidean, there