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arXiv · 2605.20585

On a question of Koll\'ar and Kov\'acs

Jihao Liu
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Abstract

We answer a question of Koll\'ar and Kov\'acs by constructing a flat projective morphism to a smooth curve whose fibers are Cohen--Macaulay and reduced, whose generic fiber is smooth, and for which the first cohomology of the structure sheaf of the fibers is not constant. The main result of this paper is obtained by generative AI, particularly Chatgpt 5.5 pro and the Rethlas system.

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Jihao Liu. 2026-05-20. On a question of Koll\'ar and Kov\'acs. https://arxiv.org/abs/2605.20585

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