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arXiv · 1304.3822

Torus Invariant Curves

Geoffrey Scott
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Abstract

Using the language of T-varieties, we study torus invariant curves on a complete normal variety $X$ with an effective codimension-one torus action. In the same way that the $T$-invariant Weil divisors on $X$ are sums of "vertical" divisors and "horizontal" divisors, so too is each $T$-invariant curve a sum of "vertical" curves and "horizontal" curves. We give combinatorial formulas that calculate the intersection between $T$-invariant divisors and $T$-invariant curves, and generalize the celebrated toric cone theorem to the case of complete complexity-one $T$-varieties.

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Geoffrey Scott. 2013-04-13. Torus Invariant Curves. https://arxiv.org/abs/1304.3822

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