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arXiv · 2412.16128

The continuity of $p$-rationality of characters and the principal block

Gunter Malle·J. Miquel Martínez·Carolina Vallejo
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Abstract

We study rationality properties of irreducible characters of finite groups. We show that the continuity of $2$-rationality is a phenomenon that can be detected in the principal $2$-block, thus refining a recent result of N. N. Hung. We also propose a conjectural group theoretical criterion for the continuity gap at level $1$ for all primes

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Gunter Malle, J. Miquel Martínez, Carolina Vallejo. 2024-12-20. The continuity of $p$-rationality of characters and the principal block. https://arxiv.org/abs/2412.16128

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