Weak crossed product orders arising from partitions of a finite group

Christos Lamprakis; Theodora Theohari-Apostolidi

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arXiv · 1909.11405

Weak crossed product orders arising from partitions of a finite group

Christos Lamprakis·Theodora Theohari-Apostolidi

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Abstract

Let R be a complete discrete valuation ring with quotient field K, L a finite Galois extension of K with Galois group G and S the integral closure of R in L. In this article, using elements of the monoid Sl(G), the set of semilinear maps of G on the set of natural numbers introduced in [8], we construct certain crossed product orders in the case that the extension S/R is unramified. We associate an element of Sl(G) to every crossed product order and give a criterion for inflating idempotent 2-cocycles.

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Christos Lamprakis, Theodora Theohari-Apostolidi. 2019-09-25. Weak crossed product orders arising from partitions of a finite group. https://arxiv.org/abs/1909.11405

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