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arXiv · 2010.06414

The automorphism group of a rational projective k*-surface

Juergen Hausen·Timo Hummel
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Abstract

We consider possibly singular rational projective k*-surfaces and provide an explicit description of the unit component of the automorphism group in terms of isotropy group orders and intersection numbers of suitable invariant curves. As an application, we characterize the almost homogeneous rational projective k*-surfaces and we specify the two-dimensional groups acting almost transitively as well as the corresponding homogeneous spaces.

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Juergen Hausen, Timo Hummel. 2020-12-01. The automorphism group of a rational projective k*-surface. https://arxiv.org/abs/2010.06414

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