Deformations of Type D Kleinian Singularities
نویسنده
چکیده
For n ≥ 4 we shall construct a family D(q) of non-commutative deformations of the coordinate algebra of a Kleinian singularity of type Dn depending on a polynomial q of degree n. We shall prove that every deformation of a type D Kleinian singularity which is not commutative is isomorphic to some D(q). We shall then consider in type D the family of deformations Oλ constructed by Crawley-Boevey and Holland. For each Oλ which is not commutative we shall exhibit an explicit isomorphism D(q) ∼= Oλ for a suitable choice of q. This will enable us to prove that every deformation of a Kleinian singularity of type Dn is isomorphic to some Oλ and determine when two Oλ are isomorphic.
منابع مشابه
Isomorphism Problems of Noncommutative Deformations of Type D Kleinian singularities
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