Separable extensions in tensor-triangular geometry and generalized Quillen stratification

Paul Balmer

doi:10.24033/asens.2298

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arXiv · 1309.1808

Separable extensions in tensor-triangular geometry and generalized Quillen stratification

Paul Balmer

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Abstract

We study the continuous map induced on spectra by a separable extension of tensor-triangulated categories. We determine the image of this map and relate the cardinality of its fibers to the degree of the extension. We then prove a weak form of descent, "up-to-nilpotence", which allows us to generalize Quillen's Stratification Theorem to equivariant derived categories.

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BibTeX RIS

Paul Balmer. 2013-09-07. Separable extensions in tensor-triangular geometry and generalized Quillen stratification. https://doi.org/10.24033/asens.2298

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