An Intrinsic Proof of Gromoll–grove Diameter Rigidity Theorem
نویسندگان
چکیده
Example 2.0. (1) Let M = CP n 2 with the classical Fubini-Study metric and diameter π2 . Let Br(p) be the metric ball of radius r and center p in CP n 2 , and let Sr(p) = ∂Br(p) be the metric sphere of radius r centered at p. It is well-known that Sπ 2 (p) is isometric to CP n 2 . The first author is supported in part by an NSF grant. Mailing Address: Department of Mathematics, University of Notre Dame, Notre Dame, IN 46556, USA; Mailing Address: Department of Mathematical Sciences, Tsinghua University, Beijing 100084, P. R. China.
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