Stable Tameness of Two-Dimensional Polynomial Automorphisms Over a Regular Ring
نویسندگان
چکیده
In this paper it is established that all two-dimensional polynomial automorphisms over a regular ring R are stably tame. This results from the main theorem of this paper, which asserts that an automorphism in any dimension n is stably tame if said condition holds point-wise over SpecR. A key element in the proof is a theorem which yields the following corollary: Over an Artinian ring A all two-dimensional polynomial automorphisms having Jacobian determinant one are stably tame, and are tame if A is a Q-algebra. Another crucial ingredient, of interest in itself, is that stable tameness is a local property: If an automorphism is locally tame, then it is stably tame.
منابع مشابه
Stable Tameness of Two-Dimensional Polynomial Automorphisms Over a Dedekind Domain
In this paper it is established that all two-dimensional polynomial automorphisms over a Dedekind Q-algebra are stably tame; in fact, they become tame with the addition of three more dimensions. A key element in the proof is this additional new theorem: Over an Artinian Q-algebra all two-dimensional polynomial automorphisms having Jacobian determinant one are tame.
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