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Quotients of Divisorial Toric Varieties

A. A'Campo-Neuen·J. Hausen
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Abstract

We consider subtorus actions on divisorial toric varieties. Here divisoriality means that the variety has many Cartier divisors like quasiprojective and smooth ones. We characterize when a subtorus action on such a toric variety admits a categorical quotient in the category of divisorial varieties. Our result generalizes previous statements for the quasiprojective case. An important tool for the proof is a universal reduction of an arbitrary toric variety to a divisorial one. This is done in terms of support maps, a notion generalizing support functions on a polytopal fan. A further essential step is the decomposition of a given subtorus invariant regular map to a divisorial variety into an invariant toric part followed by a non-toric part.

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A. A'Campo-Neuen, J. Hausen. 2002-02-26. Quotients of Divisorial Toric Varieties. https://arxiv.org/abs/math/0001131

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