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arXiv · 1806.10700

Quasi-symmetric functions and the Chow ring of the stack of expanded pairs

Jakob Oesinghaus
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Abstract

We show that the Hopf algebra of quasi-symmetric functions arises naturally as the integral Chow ring of the algebraic stack of expanded pairs originally described by J. Li, using a more combinatorial description in terms of configurations of line bundles. In particular, we exhibit a gluing map which gives rise to the comultiplication. We then apply the result to calculate the Chow rings of certain stacks of semistable curves.

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Jakob Oesinghaus. 2018-06-27. Quasi-symmetric functions and the Chow ring of the stack of expanded pairs. https://arxiv.org/abs/1806.10700

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