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Sep 24, 2013 at 12:08 vote accept HJRW
Sep 22, 2013 at 14:57 answer added Lee Mosher timeline score: 7
Sep 22, 2013 at 6:36 comment added HJRW @LeeMosher - I was referring to the fact that the curve complex is flag and so can be reconstructed easily from the curve graph. I wanted to explain the fact that some of the free-group analogues are just graphs. Next time I edit the question, I'll try to make this clearer.
Sep 22, 2013 at 3:29 comment added Lee Mosher It's misleading to say that "all the information" about the curve complex is contained in its one-skeleton. As shown by Harer, the homotopy type of the curve complex is a wedge of spheres, and this is used in establishing the v.c.d. of the mapping class group.
Sep 20, 2013 at 16:20 comment added Andy Putman @staylor : That space is useful in other contexts too. For instance, Matt Day and I used a version of it to study the Torelli subgroup of $\text{Aut}(F_n)$ in our paper The complex of partial bases for $F_n$ and finite generation of the Torelli subgroup of $\text{Aut}(F_n)$ and gave descriptions of the stabilizers of simplices in it in our paper A Birman exact sequence for $\text{Aut}(F_n)$.
Sep 20, 2013 at 14:48 comment added HJRW @staylor, Yes! The list is not meant to be exhaustive - just to indicate the scale of the problem for a non-expert interested in the area. An account of which complexes are known to be quasi-isometric to each other is exactly the sort of information that I'd be interested in.
Sep 20, 2013 at 14:40 comment added staylor Can I add to the list? The graph whose vertices are conjugacy classes of rank 1 factors and whose edges correspond to pairs of vertices represented by elements that generate a rank 2 factor is quasi-isometric to the factor complex (as are others in your list) but has local properties similar to the curve complex. For example, this graph interacts nicely with subfactor projections.
Sep 20, 2013 at 12:42 history edited HJRW CC BY-SA 3.0
Improved the readibility of the main question.
Sep 20, 2013 at 11:39 history asked HJRW CC BY-SA 3.0