| Title: | On Ricci curvature of totally real submanifolds in a quaternion projective space (English) | 
| Author: | Liu, Ximin | 
| Language: | English | 
| Journal: | Archivum Mathematicum | 
| ISSN: | 0044-8753 (print) | 
| ISSN: | 1212-5059 (online) | 
| Volume: | 38 | 
| Issue: | 4 | 
| Year: | 2002 | 
| Pages: | 297-305 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | Let $M^n$ be a Riemannian $n$-manifold. Denote by $S(p)$ and $\overline{\operatorname{Ric}}(p)$ the Ricci tensor and the maximum Ricci curvature on $M^n$, respectively. In this paper we prove that every totally real submanifolds of a quaternion projective space $QP^m(c)$ satisfies $S\le ((n-1)c+\frac{n^2}{4}H^2)g$, where $H^2$ and $g$ are the square mean curvature function and metric tensor on $M^n$, respectively. The equality holds identically if and only if either $M^n$ is totally geodesic submanifold or $n=2$ and $M^n$ is totally umbilical submanifold. Also we show that if a Lagrangian submanifold of $QP^m(c)$ satisfies $\overline{\operatorname{Ric}}=(n-1)c+\frac{n^2}{4}H^2$ identically, then it is minimal. (English) | 
| Keyword: | Ricci curvature | 
| Keyword: | totally real submanifolds | 
| Keyword: | quaternion projective space | 
| MSC: | 53C26 | 
| MSC: | 53C40 | 
| MSC: | 53C42 | 
| idZBL: | Zbl 1090.53052 | 
| idMR: | MR1942659 | 
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| Date available: | 2008-06-06T22:31:03Z | 
| Last updated: | 2012-05-10 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/107843 | 
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