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arXiv · 2605.22250

A question on klt type varieties of Han and Jiang

Jihao Liu
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Abstract

We prove that being of klt type is not an open condition in flat families of varieties. This answers a question of Han and Jiang. The construction in this paper substantially uses generative AI: the general idea for the counterexample was suggested by ChatGPT Pro 5.5, and the explicit example was found and proved by the Rethlas system.

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Jihao Liu. 2026-05-21. A question on klt type varieties of Han and Jiang. https://arxiv.org/abs/2605.22250

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