Moduli of McKay quiver representations II: Gröbner basis techniques
Moduli of McKay quiver representations II: Gröbner basis techniques
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McKay 箭袋表示的模数 II:Gröbner 基础技术
DOI:
10.1016/j.jalgebra.2007.02.014
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发表时间:
2006
影响因子:
0.9
通讯作者:
Rekha R. Thomas
中科院分区:
文献类型:
--
作者:
Alastair Craw;D. Maclagan;Rekha R. Thomas
In this paper we introduce several computational techniques for the study of moduli spaces of McKay quiver representations, making use of Gröbner bases and toric geometry. For a finite abelian group G⊂GL(n,k), let Yθbe the coherent component of the moduli space of θ-stable representations of the McKay quiver. Our two main results are as follows: we provide a simple description of the quiver representations corresponding to the torus orbits of Yθ, and, in the case where Yθequals Nakamura's G-Hilbert scheme, we present explicit equations for a cover by local coordinate charts. The latter theorem corrects the first result from Nakamura [I. Nakamura, Hilbert schemes of abelian group orbits, J. Algebraic Geom. 10 (4) (2001) 757–779]. The techniques introduced here allow experimentation in this subject and give concrete algorithmic tools to tackle further open questions. To illustrate this point, we present an example of a nonnormal G-Hilbert scheme, thereby answering a question raised by Nakamura.