S. Y. Cheng [Proc. Amer. Soc. 55 (1976), 379-381] investigated closed two-dimensional Riemannian manifolds of genus zero which admit $m$ first eigenfunctions with ...

This is a preview. Log in through your library . Abstract New error estimates for eigenvalues of symmetric integral equations are obtained. These estimates are ...

Spectral theory provides a rigorous framework for analysing the eigenvalues and eigenfunctions of differential operators that play an essential role in mathematical physics. In particular, ...

AMONG those who are trying to acquire a general acquaintance with Schrödinger's wave-mechanics there must be many who find their mathematical equipment insufficient to follow his first great ...