Estimates for eigenvalues on Riemannian manifolds

Abstract

In this paper, we investigate eigenvalues of the Dirichlet eigenvalue problem of Laplacian on a bounded domain Ω in an n-dimensional complete Riemannian manifold M. When M is an n-dimensional Euclidean space R n , the conjecture of Pólya is well known: the kth eigenvalue λ k of the Dirichlet eigenvalue problem of Laplacian satisfies λ k ⩾ 4 π 2 ( ω n vol Ω ) 2 n k 2 n , for k = 1 , 2 , … . Li and Yau [P. Li, S.T. Yau, On the Schrödinger equation and the eigenvalue problem, Comm. Math. Phys. 88 (1983) 309–318] (cf. Lieb [E. Lieb, The number of bound states of one-body Schrödinger operators and the Weyl problem, in: Proc. Sympos. Pure Math., vol. 36, 1980, pp. 241–252]) have given a partial solution for the conjecture of Pólya, that is, they have proved 1 k ∑ i = 1 k λ i ⩾ n n + 2 4 π 2 ( ω n vol Ω ) 2 n k 2 n , for k = 1 , 2 , … , which is sharp in the sense of average. In this paper, we consider a general setting for complete Riemannian manifolds. We establish an analog of the Li and Yau's inequality for eigenvalues of the Dirichlet eigenvalue problem of Laplacian on a bounded domain in a complete Riemannian manifold. Furthermore, we obtain a universal inequality for eigenvalues of the Dirichlet eigenvalue problem of Laplacian on a bounded domain in a hyperbolic space H n ( − 1 ) . From it, we prove that when the bounded domain Ω tends to H n ( − 1 ) , all eigenvalues tend to ( n − 1 ) 2 4 .