Koszulness and supersolvability for Dirichlet arrangements

Lutz, Bob

doi:10.1090/proc/14591

Koszulness and supersolvability for Dirichlet arrangements
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by Bob Lutz PDF

Proc. Amer. Math. Soc. 147 (2019), 4937-4947 Request permission

Abstract:

We prove that the cone over a Dirichlet arrangement is supersolvable if and only if its Orlik-Solomon algebra is Koszul. This was previously shown for four other classes of arrangements. We exhibit an infinite family of cones over Dirichlet arrangements that are combinatorially distinct from these other four classes.

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