CR Sub-Laplacian Comparison and Liouville-Type Theorem in a Complete Noncompact Sasakian Manifold

Autor: Jingzhi Tie, Chien Lin, Shu-Cheng Chang, Ting Jung Kuo
Rok vydání: 2018
Předmět:
Zdroj: The Journal of Geometric Analysis. 29:1676-1705
ISSN: 1559-002X
1050-6926
DOI: 10.1007/s12220-018-0056-9
Popis: In this paper, we first obtain the sub-Laplacian comparison theorem in a complete noncompact pseudohermitian manifold of vanishing torsion (i.e., Sasakian manifold). Second, we derive the subgradient estimate for positive pseudoharmonic functions in a complete noncompact pseudohermitian manifold which satisfies the CR sub-Laplacian comparison property. It functions as the CR analog of Yau’s gradient estimate. As a consequence, we have the natural CR analog of Liouville-type theorems in a complete noncompact Sasakian manifold of nonnegative pseudohermitian Ricci curvature tensors.
Databáze: OpenAIRE