Upper bounds for Steklov eigenvalues of submanifolds in Euclidean space via the intersection index (2010.12248v3)

Abstract: We obtain upper bounds for the Steklov eigenvalues $\sigma_k(M)$ of a smooth, compact, connected, $n$-dimensional submanifold $M$ of Euclidean space with boundary $\Sigma$ that involve the intersection indices of $M$ and of $\Sigma$. One of our main results is an explicit upper bound in terms of the intersection index of $\Sigma$, the volume of $\Sigma$ and the volume of $M$ as well as dimensional constants. By also taking the injectivity radius of $\Sigma$ into account, we obtain an upper bound that has the optimal exponent of $k$ with respect to the asymptotics of the Steklov eigenvalues as $k \to \infty$.