## Galilean invariance of the wave equation

This post follows James Rohlf’s Modern Physics from α to Z0 (p.104-105). See also the slides here. Start with the standard configuration for relativity. The (3+1)D space dependent Galilean transformation is The dual (1+3)D time dependent Galilean transformation is The y, z, s, and r axes are trivially invariant. Consider the one-dimensional wave equation for an …