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Orbit spaces of small tori

A. A'Campo-Neuen·J. Hausen
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Abstract

Consider an algebraic torus of small dimension acting on an open subset of a complex vector space, or more generally on a quasiaffine variety such that a separated orbit space exists. We discuss under which conditions this orbit space is quasiprojective. One of our counterexamples provides a toric variety with enough effective invariant Cartier divisors that is not embeddable into a smooth toric variety.

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A. A'Campo-Neuen, J. Hausen. 2001-10-12. Orbit spaces of small tori. https://arxiv.org/abs/math/0110133

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