Unique continuation for elliptic operators with non-multiple characteristics (Q1580495)

The paper deals with a unique continuation theorem for elliptic operators of the form \(P(D)+V(x).\) \(P(D)\) is an elliptic operator with real constant coefficients of order \(m,\) with \(2\leq m\leq n\) and \(n\leq 3\) and with simple complex characteristics; \(V(x)\) belongs to \(L^{n/m}(\mathbb R^n).\) To prove the main result of the paper, a restriction theorem for the Fourier transform to manifolds of codimension 2 is used.