Acyclic curves and group actions on affine toric surfaces

I. Arzhantsev; M. Zaidenberg

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arXiv · 1110.3028

Acyclic curves and group actions on affine toric surfaces

I. Arzhantsev·M. Zaidenberg

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Abstract

We show that every irreducible, simply connected curve on a toric affine surface X over the field of complex numbers is an orbit closure of a multiplicative group action on X. It follows that up to the action of the automorphism group Aut(X) there are only finitely many non-equivalent embeddings of the affine line in X. A similar description is given for simply connected curves in the quotients of the affine plane by small finite linear groups. We provide also an analog of the Jung-van der Kulk theorem for affine toric surfaces, and apply this to study actions of algebraic groups on such surfaces.

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BibTeX RIS

I. Arzhantsev, M. Zaidenberg. 2011-10-18. Acyclic curves and group actions on affine toric surfaces. https://arxiv.org/abs/1110.3028

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