Automorphism groups of Koras–Russell threefolds of the second kind

Original Paper


We determine the automorphism groups of Koras–Russell threefolds of the second kind. In particular we show that these groups are semi-direct products of two subgroups, one given by the multiplicative group and the other isomorphic to a polynomial ring in two variables with the addition law. We also show that these groups are generated by algebraic subgroups isomorphic to \(\mathbb {G}_{m}\) and \(\mathbb {G}_{a}\).


Automorphism groups of affine varieties Koras–Russell threefolds 

Mathematics Subject Classification

14R10 14R20 


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© The Managing Editors 2016

Authors and Affiliations

  1. 1.Institut de Mathématiques de BourgogneUniversité de Bourgogne Franche-ComtéDijon CedexFrance

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