Payne–Polya–Weinberger type inequalities for eigenvalues of nonelliptic operators

Pengcheng Niu and Huiqing Zhang

Vol. 208 (2003), No. 2, 325–345

DOI: 10.2140/pjm.2003.208.325

Abstract

In this paper we consider the eigenvalue problems for some nonelliptic operators which include the real Kohn-Laplacian in the Heisenberg and generalized Baouendi-Grushin operator. Some interest inequalities for eigenvalues are given by establishing the identities and inequalities for noncommutative vector fields.

Milestones

Received: 22 October 1999

Revised: 29 March 2002

Published: 1 February 2003