Common maxima of distance functions on orientable Alexandrov surfaces
نویسندگان
چکیده
منابع مشابه
Properties of Distance Functions on Convex Surfaces and Alexandrov Spaces
If X is a convex surface in a Euclidean space, then the squared (intrinsic) distance function dist(x, y) is d.c. (DC, delta-convex) on X×X in the only natural extrinsic sense. For the proof we use semiconcavity (in an intrinsic sense) of dist(x, y) on X × X if X is an Alexandrov space with nonnegative curvature. Applications concerning r-boundaries (distance spheres) and the ambiguous locus (ex...
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ژورنال
عنوان ژورنال: Journal of the Mathematical Society of Japan
سال: 2008
ISSN: 0025-5645
DOI: 10.2969/jmsj/06010051