PX155 - G3 - the postulates of special relativity

postulates

• einstein (1905) "on the electrodynamics of moving bodies" - foundation of SR

  • unknown whether einstein knew about the michelson-morley experiment
  • motivated by the contradictions between electromagnetism and relativity principle

• einstein started with 2 postulates:

  • RP1: the laws of physics are the same in all inertial frames
    • just galilean invariance with 'physics' generalising 'mechanics'
    • 'solves' the problem with maxwell's equations: we aren't in a special frame; all frames measure $c$
    • inconsistent with galilean velocity addition
  • RP2: the speed of light in empty space is the same in all inertial frames