Multilinear Mikhlin Multipliers with Degenerate Singularities

Abstract

We prove $L^p$ bounds for multilinear multipliers whose symbols are singular along degenerate subspaces. When the singularity has a sufficiently mild degeneracy, we show that the wavepacket analysis of the nondegenerate theory can be adapted to this setting. The admissible range of exponents depends on the geometry of the singularity.