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arXiv · 2009.14093

Permutation modules and cohomological singularity

Paul Balmer·Martin Gallauer
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Abstract

We define a new invariant of finitely generated representations of a finite group, with coefficients in a commutative noetherian ring. This invariant uses group cohomology and takes values in the singularity category of the coefficient ring. It detects which representations are controlled by permutation modules.

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Paul Balmer, Martin Gallauer. 2020-09-29. Permutation modules and cohomological singularity. https://doi.org/10.4171/cmh/534

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