Degenerate elliptic systems of pseudodifferential equations
Degenerate elliptic systems of pseudodifferential equations
Introduction.Let M be a compact C manifold and A =(a),_,..., be a matrix of pseudodifferential operators on M whose symbols, represented by local coordinates, have homogeneous asymp- totic expansions (cf.Seeley [4]).Let us consider the equation Au--f on M when A is elliptic outside a C submanifold M0 and degenerate on …