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Timeline for Diameter of m-fold cover

Current License: CC BY-SA 2.5

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Dec 6, 2009 at 3:11 comment added Anton Petrunin It seems that on this way, the best you can get is $2(m-1)d$...
Dec 5, 2009 at 22:42 comment added Anton Petrunin That is right --- it is sufficient to make it for graphs. In fact any metric space (in particular Riemannian manifold) can be approximated by a graph, say in Gromov--Hausdorff sense.
Dec 5, 2009 at 22:21 comment added Alon Amit That's right, and I modified my post to reflect that. However, I guess the point is that whatever the correct ratio is for graphs (up to subdivision, as outlined) should be the correct ratio for manifolds, right? If we can actually find a graph of diameter $d$ (say, a bipartite one to avoid the odd-cycle-diameter issue), and a connected $m$ cover with diamater $\alpha$md for $\alpha>1$, does this not also mean that the manifold case cannot be better?
Dec 5, 2009 at 22:18 history edited Alon Amit CC BY-SA 2.5
Pointed out a flaw in the graph argument.
Dec 5, 2009 at 21:05 comment added Anton Petrunin I guess that "floor" means your tree? Then it might be up to $2d$ in each floor --- not $d$...
Dec 5, 2009 at 18:12 history answered Alon Amit CC BY-SA 2.5