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Timeline for Center of convex figure

Current License: CC BY-SA 4.0

27 events
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Oct 27, 2022 at 18:27 history edited Anton Petrunin CC BY-SA 4.0
added 212 characters in body
Oct 23, 2022 at 12:33 history edited Anton Petrunin CC BY-SA 4.0
+Przesławski and Yost
Oct 23, 2022 at 12:22 history edited Anton Petrunin CC BY-SA 4.0
added 225 characters in body
S Oct 21, 2022 at 20:29 history bounty ended Anton Petrunin
S Oct 21, 2022 at 20:29 history notice removed Anton Petrunin
Oct 20, 2022 at 13:25 history edited Anton Petrunin CC BY-SA 4.0
+Huas
Oct 20, 2022 at 13:02 vote accept Anton Petrunin
S Oct 20, 2022 at 13:02 history bounty started Anton Petrunin
S Oct 20, 2022 at 13:02 history notice added Anton Petrunin Reward existing answer
Oct 20, 2022 at 11:54 comment added Anton Petrunin @fedja, this is 1-dimensional case, but I see it now --- it is true since it is true for any projection.
Oct 20, 2022 at 11:27 vote accept Anton Petrunin
Oct 20, 2022 at 11:28
S Oct 20, 2022 at 11:21 vote accept Anton Petrunin
Oct 20, 2022 at 11:27
Oct 20, 2022 at 11:14 vote accept Anton Petrunin
S Oct 20, 2022 at 11:21
Oct 20, 2022 at 1:33 answer added fedja timeline score: 2
Oct 20, 2022 at 0:01 comment added fedja @AntonPetrunin If $[a,b]$ and $[c,d]$ are $t$-close, then $a-c, b-d\le t$, so $\frac{a+b}2-\frac{c+d}2\le t$ and we can exchange the intervals to get the other bound.
Oct 19, 2022 at 23:31 answer added Saúl RM timeline score: 5
Oct 19, 2022 at 23:14 comment added Anton Petrunin @SaúlRM still, suppose two line segment are $\varepsilon$-close --- why their midpoints are $\varepsilon$-close?
Oct 19, 2022 at 22:53 comment added Saúl RM No, I hadn't thought of the barycenter of curvature. The pity is that it doesn't seem easy to check if any of these barycenters work. About the line segments, I think of their boundary as traversing the segment and then traversing it in the opposite direction, so under that definition the middle point is still the barycenter of the boundary
Oct 19, 2022 at 22:49 comment added Anton Petrunin @SaúlRM BTW it seems that for line segments only, one can choose their midpoints, but I cannot verify it.
Oct 19, 2022 at 22:46 comment added Anton Petrunin @SaúlRM did you thaut about baryceter of curvature? (In other words baryceter of vertices of polygon with weights proportional to their external angles.)
Oct 19, 2022 at 22:44 comment added Saúl RM One candidate for which I didn't find an obvious counterexample: the barycenter of the boundary of the convex set (we can parametrize the boundary by unit length and then find the barycenter of that). In segments it is just the middle point
Oct 19, 2022 at 20:13 history edited Anton Petrunin CC BY-SA 4.0
Two triangles with vertices (0,0), (1,1), (-1,1) and (0,1), (1,0), (-1,0).
S Oct 19, 2022 at 19:55 history suggested Christophe Leuridan CC BY-SA 4.0
correct spelling
Oct 19, 2022 at 19:38 answer added Christophe Leuridan timeline score: 0
Oct 19, 2022 at 17:54 comment added Christophe Leuridan I guess that take the gravity center works, but I am unable to check it. The gravity center of a non-empty compact convex set is $p_F = \lambda_F(F)^{-1} \int_F xd\lambda_F(x)$ where $\lambda_F$ is the Lebesgue measure on the affine space generated by $F$.
Oct 19, 2022 at 17:49 review Suggested edits
S Oct 19, 2022 at 19:55
Oct 18, 2022 at 12:51 history asked Anton Petrunin CC BY-SA 4.0