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arXiv · 2605.07956

Adjoint test modules along Cohen--Macaulay morphisms

Javier Carvajal-Rojas·Axel Stäbler
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Abstract

We provide a transformation rule for adjoint test modules along Cohen--Macaulay maps between Cohen--Macaulay varieties that have $F$-rational geometric fibers. This is, in part, an effective version of Enescu's theorem on the ascent of $F$-rationality under local maps with $F$-rational geometric fibers.

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Javier Carvajal-Rojas, Axel Stäbler. 2026-05-08. Adjoint test modules along Cohen--Macaulay morphisms. https://arxiv.org/abs/2605.07956

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