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arXiv · 1603.08237

Representation rings for fusion systems and dimension functions

Sune Precht Reeh·Ergün Yalçın
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Abstract

We define the representation ring of a saturated fusion system $\mathcal F$ as the Grothendieck ring of the semiring of $\mathcal F$-stable representations, and study the dimension functions of $\mathcal F$-stable representations using the transfer map induced by the characteristic idempotent of $\mathcal F$. We find a list of conditions for an $\mathcal F$-stable super class function to be realized as the dimension function of an $\mathcal F$-stable virtual representation. We also give an application of our results to constructions of finite group actions on homotopy spheres.

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Sune Precht Reeh, Ergün Yalçın. 2016-03-27. Representation rings for fusion systems and dimension functions. https://arxiv.org/abs/1603.08237

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