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arXiv · 2203.00589

Decomposition of idempotent 2-cocycles

Christos Lamprakis·Theodora Theohari-Apostolidi
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Abstract

Let L be a finite Galois extension of K with Galois group G. We decompose any idempotent 2-cocycle f using finite sequences of descending two-sided ideals of the corresponding weak crossed product algebra A:= (L/k, G, f). We specialise the results in case f is the corresponding idempotent 2-cocycle for some semilinear map from G to a multiplicative monoid with minimum element.

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Christos Lamprakis, Theodora Theohari-Apostolidi. 2022-03-01. Decomposition of idempotent 2-cocycles. https://arxiv.org/abs/2203.00589

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