A CONCAVITY CONDITION FOR EXISTENCE OF A NEGATIVE VALUE IN NEUMANN-POINCARE SPECTRUM IN THREE DIMENSIONS

초록

It is proved that if a bounded domain in three dimensions satisfies a certain concavity condition, then the Neumann-Poincare operator on either the boundary of the domain or its inversion in a sphere has a negative value in its spectrum. The concavity condition is quite simple, and is satisfied if there is a point on the boundary at which the Gaussian curvature is negative.

키워드