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arXiv · 2411.16883

Chow theory of toric variety bundles

Francesca Carocci·Leonid Monin·Navid Nabijou
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Abstract

We describe the Chow homology and cohomology of toric variety bundles, with no restrictions on the singularities of the fibre. We present the ordinary and equivariant homologies as modules over the cohomology of the base, identify the ordinary cohomology with homology-valued Minkowski weights, and identify the equivariant cohomology with cohomology-weighted piecewise polynomial functions. We describe the product structure on Minkowski weights via a fan displacement rule, and the non-equivariant limit via equivariant multiplicities. Along the way we establish relative analogues of the K\"unneth property and Kronecker duality. Applications include the balancing condition in logarithmic enumerative geometry.

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Francesca Carocci, Leonid Monin, Navid Nabijou. 2024-11-25. Chow theory of toric variety bundles. https://arxiv.org/abs/2411.16883

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