Sharp bounds for the first two eigenvalues of an exterior Steklov eigenvalue problem
arXiv:2304.11297
Abstract
Let () be an exterior Euclidean domain with smooth boundary . We consider the Steklov eigenvalue problem on . First we derive a sharp lower bound for the first eigenvalue in terms of the support function and the distance function to the origin of . Second under various geometric conditions on we obtain sharp upper bounds for the first eigenvalue. Along the proof, we get a sharp upper bound for the capacity of when and is connected. Last we also discuss an upper bound for the second eigenvalue.
28 pages; all comments are welcome. In v2, typos are corrected; minor modifications are done with no essential changes