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Sharp bounds on the number of scattering poles for perturbations of the Laplacian. (English) Zbl 0766.35032
Author’s summary: Sharp bounds on the number $N(r)$ of the scattering poles in the disc $\vert z\vert\leq r$ for large class of compactly supported perturbations (not necessarily selfadjoint) of the Laplacian in $\bbfR\sp n$, $n\geq 3$, odd, are obtained. In particular, in the elliptic case the estimate $N(r)\leq Cr\sp n+C$ is proved.

##### MSC:
 35P25 Scattering theory (PDE) 35J05 Laplacian operator, reduced wave equation (Helmholtz equation), Poisson equation 47A40 Scattering theory of linear operators
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##### References:
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