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arXiv · 1907.02694

Non-Ulrich representation type

Daniele Faenzi·Francesco Malaspina·Giangiacomo Sanna
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Abstract

We show that a smooth projective non-degenerate arithmetically Cohen-Macaulay subvariety X of P^N infinite Cohen-Macaulay type becomes of finite Cohen-Macaulay type by removing Ulrich bundles if and only if N = 5 and X is a quartic scroll or the Segre product of a line and a plane. In turn, we give a complete and explicit classification of ACM bundles over these varieties.

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Daniele Faenzi, Francesco Malaspina, Giangiacomo Sanna. 2019-07-05. Non-Ulrich representation type. https://arxiv.org/abs/1907.02694

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