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arXiv · 2605.30223

Hodge numbers of moduli of principal bundles on a curve

Chiu-Chu Melissa Liu·Florent Schaffhauser
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Abstract

We prove an inversion theorem for recursive formulas satisfied by certain families of converging power series in two variables. These power series are indexed by the Harder-Narasimhan types of principal $G$-bundles of degree $d \in π_1 G$ on a smooth projective curve $X$, where $G$ is a connected complex reductive group. As an application, we obtain a closed formula for the Hodge-Poincaré series of moduli stacks of semistable principal $G$-bundles of degree $d$. We also compute the variation of Hodge structure of the moduli stack of all principal $G$-bundles over $X$, as a function of the period matrix of that curve.

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Chiu-Chu Melissa Liu, Florent Schaffhauser. 2026-05-28. Hodge numbers of moduli of principal bundles on a curve. https://arxiv.org/abs/2605.30223

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