Regularity in time of the time-dependent Maxwell equations

We study the regularity in time of the solution to the time-dependent Maxwell equations, in the vacuum bounded by a perfect conductor and without charges. First, we recall the results derived from the classical theory when the domain has a Lipschitz boundary. Then, when it is a polyhedron, we extend the results to both the regular and singular parts of the electromagnetic field. Last, when it is a polygon, we improve those results concerning the singular part of the field.