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arXiv · 1408.2524

Restriction to finite-index subgroups as \'etale extensions in topology, KK-theory and geometry

Paul Balmer·Ivo Dell'Ambrogio·Beren Sanders
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Abstract

For equivariant stable homotopy theory, equivariant KK-theory and equivariant derived categories, we show how restriction to a subgroup of finite index yields a finite commutative separable extension, analogous to finite \'etale extensions in algebraic geometry.

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Paul Balmer, Ivo Dell'Ambrogio, Beren Sanders. 2014-08-11. Restriction to finite-index subgroups as \'etale extensions in topology, KK-theory and geometry. https://arxiv.org/abs/1408.2524

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