Characterizing Multigraded Regularity on Products of Projective Spaces

Autor: Bruce, Juliette, Heller, Lauren Cranton, Sayrafi, Mahrud
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Popis: We explore the relationship between multigraded Castelnuovo-Mumford regularity, truncations, Betti numbers, and virtual resolutions. We prove that on a product of projective spaces $X$, the multigraded regularity region of a module $M$ is determined by the minimal graded free resolutions of the truncations $M_{\geq\mathbf{d}}$ for $\mathbf{d}\in\operatorname{Pic}X$. Further, by relating the minimal graded free resolutions of $M$ and $M_{\geq\mathbf{d}}$ we provide a new bound on multigraded regularity of $M$ in terms of its Betti numbers. Using this characterization of regularity and this bound we also compute the multigraded Castelnuovo-Mumford regularity for a wide class of complete intersections.
29 pages; this version adds missing assumptions to Proposition 3.5
Databáze: OpenAIRE