These are the Maxwell's Equations we will be using to solve for regions "I" and "II" in our approximation of the Michelson interferometer.
Gauss' Law:
∇ ⋅ E = 0 {\displaystyle {\boldsymbol {\nabla \cdot E}}=0}
Gauss' Law for Magnetism:
∇ ⋅ B = 0 {\displaystyle {\boldsymbol {\nabla \cdot B}}=0}
Faradays's Law:
∇ × E + ∂ B ∂ t = 0 {\displaystyle {\boldsymbol {\nabla \times E}}+{\frac {\partial {\boldsymbol {B}}}{\partial t}}=0}
Ampere's Law:
∇ × B − μ 0 ϵ 0 ∂ E ∂ t = 0 {\displaystyle {\boldsymbol {\nabla \times B}}-\mu _{0}\epsilon _{0}{\frac {\partial {\boldsymbol {E}}}{\partial t}}=0}