Demushkin's Theorem in Codimension One

2002/09/30 by Florian Berchtold, Juergen Hausen
Mathematics · #math.AG #math.AC #msc:13A50 #msc:14L30 #msc:14M25 #msc:14R20

paper · pdf

published as Math. Z. 244, No. 4, 697-703 (2003) · 6 pages, to appear in Math. Z

arxiv created 2002/09/30 · arxiv updated 2009/11/30

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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