Abstract
Given a collection of subspaces in an -dimensional vector space we can associate to them linear ideals in the symmetric algebra . Conca and Herzog showed that the Castelnuovo–Mumford regularity of the product of linear ideals is equal to . Derksen and Sidman showed that the Castelnuovo–Mumford regularity of the intersection of linear ideals is at most . We show that analogous results hold when we work over the exterior algebra (over a field of characteristic 0). To prove these results we rely on the functoriality of equivariant free resolutions and construct a functor from the category of polynomial functors to itself. The functor transforms resolutions of polynomial functors associated to subspace arrangements over the symmetric algebra to resolutions over the exterior algebra.
Citation
Francesca Gandini. "Resolutions of ideals of subspace arrangements." J. Commut. Algebra 14 (3) 319 - 338, Fall 2022. https://doi.org/10.1216/jca.2022.14.319
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