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arXiv · 2605.22782

Boundedness of total Cartier indices for rational singularities in families

Jihao Liu·Ruicheng Hu·Sheng Qin
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Abstract

We show that the total Cartier index of varieties with rational singularities in a bounded family is bounded. This solves a problem of Han and Jiang. The overall structure of the proof, which treats the surface case and the higher-dimensional case separately, was originated by generative AI, particularly the Rethlas system, and was substantially corrected and elaborated by hand.

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Jihao Liu, Ruicheng Hu, Sheng Qin. 2026-05-21. Boundedness of total Cartier indices for rational singularities in families. https://arxiv.org/abs/2605.22782

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