Regularity in codimension one of orbit closures in module varieties
نویسنده
چکیده
Let Md(k) denote the space of d×d-matrices with coefficients in an algebraically closed field k. Let X be an orbit closure in the product [Md(k)] t equipped with the action of the general linear group GLd(k) by simultaneous conjugation. We show that X is regular at any point y such that the orbit of y has codimension one in X. The proof uses mainly the representation theory of associative algebras.
منابع مشابه
N ov 2 00 4 Orbit closures for representations of Dynkin quivers are regular in codimension two
We develop reductions for classifications of singularities of orbit closures in module varieties. Then we show that the orbit closures for representations of Dynkin quivers are regular in codimension two.
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