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arXiv · 1908.06680

Arbitrarily large $\mathcal{O}$-Morita Frobenius numbers

Michael Livesey
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Abstract

We construct blocks of finite groups with arbitrarily large $\mathcal{O}$-Morita Frobenius numbers. There are no known examples of two blocks defined over $\mathcal{O}$ that are not Morita equivalent but the corresponding blocks defined over $k$ are. Therefore, the above strongly suggests that Morita Frobenius numbers are also unbounded, which would answer a question of Benson and Kessar.

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Michael Livesey. 2019-08-19. Arbitrarily large $\mathcal{O}$-Morita Frobenius numbers. https://arxiv.org/abs/1908.06680

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