Frontiers of Mathematics in China

, Volume 9, Issue 2, pp 417–423 | Cite as

Radius of locally convex subsets in Alexandrov spaces with curvature ⩾ 1 and radius > π/2

Research Article


Let X be a complete Alexandrov space with curvature ⩾ 1 and radius > π/2. We prove that any connected, complete, and locally convex subset without boundary in X also has the radius > π/2.


Alexandrov space convex subset radius 


53C20 53C35 


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Copyright information

© Higher Education Press and Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.School of Mathematical Sciences (and the Key Laboratory on Mathematics and Complex System)Beijing Normal UniversityBeijingChina
  2. 2.Center of Mathematical SciencesZhejiang UniversityHangzhouChina

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