{ "id": "1009.3084", "version": "v2", "published": "2010-09-16T03:24:27.000Z", "updated": "2012-05-01T00:41:38.000Z", "title": "Resolvent at low energy III: the spectral measure", "authors": [ "Colin Guillarmou", "Andrew Hassell", "Adam Sikora" ], "comment": "42 pages, 4 figures", "categories": [ "math.AP", "math.SP" ], "abstract": "Let $M^\\circ$ be a complete noncompact manifold and $g$ an asymptotically conic Riemaniann metric on $M^\\circ$, in the sense that $M^\\circ$ compactifies to a manifold with boundary $M$ in such a way that $g$ becomes a scattering metric on $M$. Let $\\Delta$ be the positive Laplacian associated to $g$, and $P = \\Delta + V$, where $V$ is a potential function obeying certain conditions. We analyze the asymptotics of the spectral measure $dE(\\lambda) = (\\lambda/\\pi i) \\big(R(\\lambda+i0) - R(\\lambda - i0) \\big)$ of $P_+^{1/2}$, where $R(\\lambda) = (P - \\lambda^2)^{-1}$, as $\\lambda \\to 0$, in a manner similar to that done previously by the second author and Vasy, and by the first two authors. The main result is that the spectral measure has a simple, `conormal-Legendrian' singularity structure on a space which is obtained from $M^2 \\times [0, \\lambda_0)$ by blowing up a certain number of boundary faces. We use this to deduce results about the asymptotics of the wave solution operators $\\cos(t \\sqrt{P_+})$ and $\\sin(t \\sqrt{P_+})/\\sqrt{P_+}$, and the Schr\\\"odinger propagator $e^{itP}$, as $t \\to \\infty$. In particular, we prove the analogue of Price's law for odd-dimensional asymptotically conic manifolds. This result on the spectral measure has been used in a follow-up work by the authors (arXiv:1012.3780) to prove sharp restriction and spectral multiplier theorems on asymptotically conic manifolds.", "revisions": [ { "version": "v2", "updated": "2012-05-01T00:41:38.000Z" } ], "analyses": { "subjects": [ "35P25", "47A40", "58J50" ], "keywords": [ "spectral measure", "low energy", "complete noncompact manifold", "asymptotically conic riemaniann metric", "wave solution operators" ], "note": { "typesetting": "TeX", "pages": 42, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1009.3084G" } } }