Special Relativity (English) Special Relativity, Lecture 3: Simultaneity and Causality (English) December 4, 2015 Teach Yourself Special Relativity with Dr. Pervez Hoodbhoy Lecture 3: Simultaneity and Causality 1. Synchronizing clocks 2. Why simultaneity is relative 3. Revisit length contraction and time dilation 4. The invariant interval 5. Causality