Microlocal analysis for differential operators

Written in the tradition of Lars Hörmander, this compact primer introduces microlocal analysis within the traditional study of partial differential equations. The field has found uses in harmonic analysis, complex analysis, and theoretical physics. Grigis and Sjöstrand concentrate on foundational techniques, most notably the stationary phase method. Along the way they cover wavefront sets, elliptic operators, local symplectic geometry, and WKB constructions.