Sá Barreto, Antônio Second microlocal ellipticity and propagation of conormality for semilinear wave equations. (English) Zbl 0746.35021 J. Funct. Anal. 102, No. 1, 47-71 (1991). The author considers three problems on the propagation of conormal singularities for semilinear wave equations: the evolution of two simply tangent waves, the interaction of three conormal waves, and the evolution of one wave with a cusp singularity. He uses quasihomogeneous blow-ups to reduce the geometries to normal crossing and show that the lift of the operator by these blow-down maps is elliptic in some directions of the compressed cotangent bundle of the blown-up manifold. This leads to a strengthening of the previously known results and a simplification of their proofs. Reviewer: Chen Shuxing (Shanghai) Cited in 7 Documents MSC: 35L65 Hyperbolic conservation laws 35A27 Microlocal methods and methods of sheaf theory and homological algebra applied to PDEs 58J47 Propagation of singularities; initial value problems on manifolds 35L05 Wave equation Keywords:conormal singularities; evolution of two simply tangent waves; interaction of three conormal waves; wave with a cusp singularity; quasihomogeneous blow-ups PDFBibTeX XMLCite \textit{A. Sá Barreto}, J. Funct. Anal. 102, No. 1, 47--71 (1991; Zbl 0746.35021) Full Text: DOI References: [1] Arnol’d, V. I., Wave fronts evolution and equivariant Morse lemma, Comm. Pure Appl. Math., 28, 557-582 (1976) · Zbl 0343.58003 [5] Bony, J.-M, Second microlocalization and propagation of singularities for semilinear hyperbolic equations, (Taniguchi Symp. HERT. Taniguchi Symp. HERT, Katata (1984)), 11-49 · Zbl 0669.35073 [6] Chemin, J.-Y, Interaction des trois ondes dans les équations semilinéaires strictment hyperboliques d’ordre 2, Comm. Partial Differential Equations, 12, No. 11, 1203-1225 (1987) · Zbl 0651.35049 [7] Hörmander, L., (The Analysis of Linear Partial Differential Operators, Vol. 3 (1985), Springer-Verlag: Springer-Verlag Berlin) · Zbl 0612.35001 [9] Melrose, R., Semilinear equations with cusp singularities, Jour. equations deriv. partielles, St. Jean de Monts (1987) · Zbl 0656.35098 [11] Melrose, R.; Ritter, N., Interactions of nonlinear progressing waves for semilinear wave equations, Ann. of Math., 121, 187-213 (1985) · Zbl 0575.35063 [12] Melrose, R.; Ritter, N., Interaction of nonlinear progressing waves for semilinear wave equations, II, Ark. Mat., 25, 91-114 (1987) · Zbl 0653.35058 [15] Ritter, N., Progressing Wave Solutions to Nonlinear Cauchy Problems, MIT Thesis (June 1984) [16] SáBarreto, A., Interactions of conormal waves for fully semilinear wave equations, J. Funct. Anal., 89, 233-273 (1990) · Zbl 0726.35083 This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.