Departamento de Análisis Matemático, Universidad de La Laguna, 38271 Canary Islands, Spain ; Departamento de Análisis Matemático, Universidad de La Laguna, 38271 Canary Islands, Spain
Abstract:
Let be a complete Riemannian manifold of dimension without boundary and with Ricci curvature bounded below by where If is a vector field such that and on for some nonnegative constants and then we show that any positive solution of the equation satisfies the estimate
on , for all In particular, for the case when this estimate is advantageous for small values of and when it recovers the celebrated Liouville theorem of Yau (Comm. Pure Appl. Math.28 (1975), 201-228).