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arXiv · 2506.03745

Real Toric Varieties: Interactions between their Geometry and their Topology

Jules Chenal·Matilde Manzaroli
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Abstract

In the present article, we investigate the topology of real toric varieties, especially those whose torus is not split over the field of real numbers. We describe some canonical fibrations associated to their real loci. Then, we establish various properties of their cohomology provided that their real loci are compact and smooth. For instance, we compute their Betti numbers, show that their cohomology is totally algebraic, and extend a criterion of orientability. In addition, we provide the topological classification of equivariant embeddings of non-split tridimensional tori.

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Jules Chenal, Matilde Manzaroli. 2025-06-04. Real Toric Varieties: Interactions between their Geometry and their Topology. https://arxiv.org/abs/2506.03745

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