Minimal singularities in orbit closures of matrix pencils. (English) Zbl 1064.16012
Summary: We show that all singularities occurring in minimal degenerations of matrix pencils are Cohen-Macaulay and regular in codimension 1.
MSC:
16G20 | Representations of quivers and partially ordered sets |
14L30 | Group actions on varieties or schemes (quotients) |
14M05 | Varieties defined by ring conditions (factorial, Cohen-Macaulay, seminormal) |
Keywords:
matrix pencils; orbit closures; singularities; Kronecker algebras; path algebras of quivers; module varieties; degenerationsReferences:
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