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arXiv · math/0502240

Syzygies, multigraded regularity and toric varieties

Abstract

Using multigraded Castelnuovo-Mumford regularity, we study the equations defining a projective embedding of a variety X. Given globally generated line bundles B_1, ..., B_k on X and integers m_1, ..., m_k, consider the line bundle L := B_1^m_1 \otimes ... \otimes B_k^m_k. We give conditions on the m_i which guarantee that the ideal of X in P(H^0(X,L)) is generated by quadrics and the first p syzygies are linear. This yields new results on the syzygies of toric varieties and the normality of polytopes.

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BibTeXRIS

Milena Hering, Hal Schenck, Gregory G. Smith. 2006-08-09. Syzygies, multigraded regularity and toric varieties. https://doi.org/10.1112/s0010437x0600251x

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