# On the estimate of first positive eigenvalue of a sublaplacian in a pseudohermitian manifold

Yen Wen Fan, Ting Jung Kuo

1 引文 斯高帕斯（Scopus）

## 摘要

In this paper, we first obtain a CR version of Yau's gradient estimate for eigenfunc- tions of a sublaplacian. Second, by using CR analogue of Li-Yau's eigenvalue estimate, we are able to obtain a lower bound of the first positive eigenvalue in a pseudohermitian manifold of nonvanishing pseudohermitian torsion and nonpositive lower bound on pseudohermitian Ricci curvature.

原文 英語 929-946 18 Asian Journal of Mathematics 18 5 https://doi.org/10.4310/AJM.2014.v18.n5.a7 已發佈 - 2014 是

• 數學(全部)
• 應用數學