A sharp estimate for Neumann eigenvalues of the Laplace–Beltrami operator for domains in a hemisphere
Rafael D. Benguria, Barbara Brandolini, Francesco Chiacchio · Communications in Contemporary Mathematics · 2019
Here, we prove an isoperimetric inequality for the harmonic mean of the first [Formula: see text] non-trivial Neumann eigenvalues of the Laplace–Beltrami operator for domains contained in a hemisphere of [Formula: see text].