Automorphism groups of Koras–Russell threefolds of the second kind

  • Charlie PetitjeanEmail author
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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