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arXiv · 2512.22432

Divisorial fans and algebraic torus actions over arbitrary fields

Gary Martinez-Nunez
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Abstract

We provide an algebro-geometric combinatorial description of normal varieties endowed with an effective action of an algebraic torus over arbitrary fields. This description is achieved in terms of divisorial fans endowed with a Galois semilinear action. This work concludes the description of normal $T$-varieties over fields.

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Gary Martinez-Nunez. 2025-12-27. Divisorial fans and algebraic torus actions over arbitrary fields. https://arxiv.org/abs/2512.22432

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