Algebraic rational cells and equivariant intersection theory

Richard Gonzales

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arXiv · 1404.2486

Algebraic rational cells and equivariant intersection theory

Richard Gonzales

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Abstract

We provide a notion of algebraic rational cell with applications to intersection theory on singular varieties with torus action. Based on this notion, we study the algebraic analogue of $\mathbb{Q}$-filtrable varieties: algebraic varieties where a torus acts with isolated fixed points, such that the associated Bialynicki-Birula decomposition consists of algebraic rational cells. We show that the rational equivariant Chow group of any $\mathbb{Q}$-filtrable variety is freely generated by the cell closures. We apply this result to group embeddings, and more generally to spherical varieties. This paper is an extension of arxiv.org/abs/1112.0365 to equivariant Chow groups.

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Richard Gonzales. 2014-04-09. Algebraic rational cells and equivariant intersection theory. https://arxiv.org/abs/1404.2486

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