What are estimates of L^2-norms of derivatives of any order for eigenfunction of the Dirichlet Laplacian?

I need upper bounds for the norm in L^2 of a function u such that -\Delta u=\lambda u on \Omega, u vanishes on the boundary. If the set \Omega is a polyhedron we have that this norm equals(!)...

08 February 2019 9,853 0 View