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arXiv · 0811.0626

Canonical divisors on T-varieties

Hendrik Süß
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Abstract

Generalising toric geometry we study compact varieties admitting lower dimensional torus actions. In particular we describe divisors on them in terms of convex geometry and give a criterion for their ampleness. These results may be used to study Fano varieties with small torus actions. As a first result we classify log del Pezzo C*-surfaces of Picard number 1 and Gorenstein index less than 4. In further examples we show how classification might work in higher dimensions and we give explicit descriptions of some equivariant smoothings of Fano threefolds.

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Hendrik Süß. 2008-11-05. Canonical divisors on T-varieties. https://arxiv.org/abs/0811.0626

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