arXiv 0801.06602008-01-04math-phmath.MPmath.SP

Resonances and balls in obstacle scattering with Neumann boundary conditions

T. J. Christiansen

英文摘要：

We consider scattering by an obstacle in $\Real^d$, $d\geq 3 $ odd. We show that for the Neumann Laplacian if an obstacle has the same resonances as the ball of radius $ρ$ does, then the obstacle is a ball of radius $ρ$. We give related results for obstacles which are disjoint unions of several balls of the same radius.

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