Astérisque 2013; 136 pp; softcover Number: 351 ISBN13: 9782856293676 List Price: US$52 Member Price: US$41.60 Order Code: AST/351
 The authors consider the fundamental solution to the wave equation on a manifold with corners of arbitrary codimension. If the initial pole of the solution is appropriately situated, the authors show that the singularities which are diffracted by the corners (i.e., loosely speaking, are not propagated along limits of transversely reflected rays) are smoother than the main singularities of the solution. More generally, the authors show that subject to a hypothesis of nonfocusing, diffracted wavefronts of any solution to the wave equation are smoother than the incident singularities. These results extend the authors' previous work on edge manifolds to a situation where the fibers of the boundary fibration, obtained here by blowup of the corner in question, are themselves manifolds with corners. A publication of the Société Mathématique de France, Marseilles (SMF), distributed by the AMS in the U.S., Canada, and Mexico. Orders from other countries should be sent to the SMF. Members of the SMF receive a 30% discount from list. Readership Graduate students and research mathematicians interested in wave equations, wavefront sets, and diffraction. Table of Contents  Introduction
 Geometry: metric and Laplacian
 Bundles and bicharacteristics
 Edgeb calculus
 Differentialpseudodifferential operators
 Coisotropic regularity and nonfocusing
 Edge propagation
 Propagation of fiberglobal coisotropic regularity
 Geometric theorem
 Index of notation
 Bibliography
