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arXiv · 2406.12737

Regular algebras of dimension four associated to coordinate rings of rank-two quadrics

R. G. Chandler·H. Tran·P. Veerapen·X. Wang
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Abstract

In this paper, we classify connected graded quadratic Artin-Schelter regular (AS-regular, henceforth) algebras of global dimension four that have a Hilbert series the same as that of the polynomial ring on four generators and that map onto a twisted homogeneous coordinate ring of a rank-two quadric. A twisted homogeneous coordinate ring is a construction that was defined by Artin, Tate, and Van den Bergh in \cite{ATV1, ATV2, AVdB1990} in the context of the classification of AS-regular algebras of global dimension three. In \cite{SV99,VVr}, the authors classified AS-regular algebras of global dimension four that map onto the twisted homogeneous coordinate ring of a rank-three and a rank-four quadric, respectively. We expand on their work to include the case of coordinate rings of a rank-two quadric.

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R. G. Chandler, H. Tran, P. Veerapen, X. Wang. 2024-06-18. Regular algebras of dimension four associated to coordinate rings of rank-two quadrics. https://arxiv.org/abs/2406.12737

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