The integral Chow ring of $\mathscr{M}_{0}(\mathbb{P}^r, 2)$

Renzo Cavalieri; Damiano Fulghesu

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arXiv · 2604.19713

The integral Chow ring of $\mathscr{M}_{0}(\mathbb{P}^r, 2)$

Renzo Cavalieri·Damiano Fulghesu

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Abstract

We compute a presentation for the integral Chow rings of the moduli stacks of degree $2$ maps from smooth rational curves to projective space $\mathbb{P}^r$, as a quotient of a three-variable polynomial ring. The relations as $r$ varies have rich combinatorial structure: all non-trivial relations are encoded by two generating functions which are rational functions.

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Renzo Cavalieri, Damiano Fulghesu. 2026-04-21. The integral Chow ring of $\mathscr{M}_{0}(\mathbb{P}^r, 2)$. https://arxiv.org/abs/2604.19713

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