Maxwell's equations in a polyhedron: a density result

In this Note, it is proven that, in a polyhedral domain Omega of R-3, smooth fields are dense in the subspaces of H (curl, div; Omega) whose elements have either their tangential trace, or their normal trace, in L-2(partial derivative Omega). To that aim, an explicit knowledge of the singularities of the Laplacian is required. This should allow to solve with nodal, H-1-conforming, finite elements, Maxwell's equations with an impedance condition on the boundary. The proofs are detailed in [8] (in French). (C) Academie des Sciences/Elsevier, Paris.