• Holomorphic Two-Spheres in the Complex Grassmann Manifold $G(k, n)$

• # Fulltext

https://www.ias.ac.in/article/fulltext/pmsc/122/03/0399-0409

• # Keywords

Moving frame; totally geodesic; Gaussian curvature.

• # Abstract

In this paper, we study the non-degenerate holomorphic $S^2$ in the complex Grassmann manifold $G(k,n), 2k\leq n$, by the method of moving frame. For a non-degenerate holomorphic one, there exists globally defined positive functions $\lambda_1,\ldots,\lambda_k$ on $S^2$. We first show that the holomorphic $S^2$ in $G(k, 2k)$ is totally geodesic if these $\,\lambda_i$ are all equal. Conversely, for any totally geodesic immersion 𝑓 from $S^2$ into $G(k, n)$, we prove that $f(S^2)\subset G(k, 2k)$ up to $U(n)$-transformation, $\lambda_i=\frac{1}{\sqrt{k}}$, the Gaussian curvature $K=\frac{4}{k}$ and 𝑓 is given by $(z_0,z_1)\mapsto(z_0 I_k,z_1 I_k,0)$, in terms of homogeneous coordinate.

• # Author Affiliations

1. School of Mathematical Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
2. Department of Mathematics, University of Science and Technology of China, Hefei, Anhui 230026, People’s Republic of China

• # Proceedings – Mathematical Sciences

Volume 130, 2020
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019