In this paper we prove that the second eigenvalue of the Laplacian
for a spherical band on the unit sphere S2 has multiplicity 2. We also show
that among all spherical bands of given fixed area less than 2π the second
eigenvalue is maximized at the band which is symmetrical with respect to the
equator.
Relation:
Proceedings of the American Mathematical Society 132(1), pp.157-164
