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arXiv · 2601.16415

Chow rings of moduli spaces of genus 0 curves with collisions

William C. Newman
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Abstract

Introduced in [BB], simplicially stable spaces are alternative compactifications of $\mathcal{M}_{g,n}$ generalizing Hassett's moduli spaces of weighted stable curves. We give presentations of the Chow rings of these spaces in genus $0$ using techniques developed by the author in [New25]. When considering the special case of $\overline{\mathcal{M}}_{0,n}$, this gives a new proof of Keel's presentation of $\operatorname{CH}(\overline{\mathcal{M}}_{0,n})$.

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William C. Newman. 2026-01-23. Chow rings of moduli spaces of genus 0 curves with collisions. https://arxiv.org/abs/2601.16415

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