2.3. Galileian relativity in electromagnetism

Einstein’s relativity arises in electromagnetism, in order for the equations to be compatible with the experimental observation of finite speed of light and equal for every inertial observer (Michelson and Morley), and to be invariant under Lorentz’s transfomrations.

Relativity in electromagnetism is treated in the framework of Einstein’s theory of Special Relativity.

Relativity in classical electromagnetism is derived from balance equations of electromagnetism in free space for arbitrary domains and - maybe better - from electromagnetism in matter for arbitrary domains: these transformations are compared with Taylor expansion of Lorentz’s transformations for “small” value of \(|\vec{v}|/c\) ratio.