The Nori–Hilbert scheme is not smooth for 2-Calabi–Yau algebras
Raf Bocklandt
University of Amsterdam, NetherlandsFederica Galluzzi
Università di Torino, ItalyFrancesco Vaccarino
Politecnico di Torino, Italy
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Abstract
Let be an algebraically closed field of characteristic zero and let be a finitely generated -algebra. The Nori–Hilbert scheme of , , parameterizes left ideals of codimension in . It is well known that is smooth when is formally smooth.
In this paper we will study for 2–Calabi–Yau algebras. Important examples include the group algebra of the fundamental group of a compact orientable surface of genus , and preprojective algebras. For the former, we show that the Nori–Hilbert scheme is smooth only for , while for the latter we show that a component of containing a simple representation is smooth if and only if it only contains simple representations. Under certain conditions, we generalize this last statement to arbitrary 2-Calabi–Yau algebras.
Cite this article
Raf Bocklandt, Federica Galluzzi, Francesco Vaccarino, The Nori–Hilbert scheme is not smooth for 2-Calabi–Yau algebras. J. Noncommut. Geom. 10 (2016), no. 2, pp. 745–774
DOI 10.4171/JNCG/247