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Apr
9
comment is there any relationship between the convexity radii of two “near” points in a riemannian manifold?
Ok, I got some sort of an answer from klingenberg, riemannian geometry, page 85, corollary 1.9.11: the convexity radius (with a different and stronger definition) is lipschitz, with lipschitz constant at most 1!
Apr
8
revised is there any relationship between the convexity radii of two “near” points in a riemannian manifold?
edited title
Apr
8
asked is there any relationship between the convexity radii of two “near” points in a riemannian manifold?
Jan
13
comment Is the diameter of the geodesic closure of a set B bounded purely in therm of the diameter of B?
hey! I probably found a counterexample just now XD! Consider the following metric graph: the vertex set is \Z_4 \times \N. and the edges are.. 1) ..of type [(m, n), (m+1, n)] for every m \in \Z_4, n \in \N 2) .. of type [(0, n), (1, n+1)], [(1, n+1), (2, n)], [(2, n), (3, n+1)], [(3, n+1), (0, n)] B := \Z_4 \times {0}
Jan
13
asked Is the diameter of the geodesic closure of a set B bounded purely in therm of the diameter of B?
Nov
7
revised Action of groups on graphs
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Nov
7
comment Action of groups on graphs
yes it is correct. Thank you!
Nov
7
revised Action of groups on graphs
added 440 characters in body
Nov
7
asked Action of groups on graphs
Jul
20
revised what's the exact definition of “framing” of a SATELLITE link?
added 271 characters in body
Jul
20
asked what's the exact definition of “framing” of a SATELLITE link?
May
19
awarded  Scholar
May
19
accepted question from hatcher basic 3 manifolds
May
17
comment question from hatcher basic 3 manifolds
wow! I think this is a correct answer! I wonder why hatcher gave no details of this fact. thanks!
May
17
awarded  Commentator
May
17
comment question from hatcher basic 3 manifolds
so what? what is the implication of your observation?
May
17
revised question from hatcher basic 3 manifolds
added 109 characters in body
May
17
asked question from hatcher basic 3 manifolds
Apr
6
awarded  Tumbleweed
Mar
31
revised is a free cellular action of a discrete group over a cellular complex always properly discontinuous?
edited tags