Summary of Material in Chapters 4-6

• event, world line, line of simultaneity
• inertial reference frame, principle of relativity
• spacelike and timelike intervals, proper time
• four-vector
• inertial force, centrifugal force, centripetal acceleration
• equivalence principle

• spacetime diagrams and their use
• spacetime Pythagorean theorem
• collocation and simultaneity in Einsteinian relativity
• time dilation and twin paradox
• Lorentz contraction
• the representation of waves in spacetime -- wave four-vector
• the dispersion relation for relativistic waves and associated concepts such as the phase and group velocities of these waves
• the relativistic Doppler effect
• the relativistic addition of velocities
• circular motion
• acceleration in special relativity -- how our view of acceleration differs between different inertial reference frames
• accelerated reference frames, equivalence principle, gravitational red shift, event horizons