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arXiv · 1507.06087

Automorphism groups of Koras-Russell threefolds of the second kind

Charlie Petitjean
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Abstract

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 Gm and Ga.

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Charlie Petitjean. 2015-07-22. Automorphism groups of Koras-Russell threefolds of the second kind. https://arxiv.org/abs/1507.06087

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