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Demushkin's Theorem in Codimension One

Florian Berchtold·Juergen Hausen
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Abstract

Demushkin's Theorem says that any two toric structures on an affine variety X are conjugate in the automorphism group of X. We provide the following extension: Let an (n-1)-dimensional torus T act effectively on an n-dimensional affine toric variety X. Then T is conjugate in the automorphism group of X to a subtorus of the big torus of X.

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Florian Berchtold, Juergen Hausen. 2002-09-30. Demushkin's Theorem in Codimension One. https://arxiv.org/abs/math/0209405

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