|
Let K be a 2–dimensional finite flag complex. We study the CAT(0)
dimension of the `Bestvina–Brady group', or `Artin kernel',
ΓK. We show that ΓK has CAT(0)
dimension 3 unless K admits a piecewise Euclidean metric of non-positive
curvature. We give an example to show that this implication cannot
be reversed. Different choices of K lead to examples where the CAT(0)
dimension is 3, and either (i) the geometric dimension is 2, or (ii) the
cohomological dimension is 2 and the geometric dimension is not known.
|