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arXiv · 1905.08984

Topological cyclic homology

Lars Hesselholt·Thomas Nikolaus
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Abstract

This survey of topological cyclic homology is a chapter in the Handbook on Homotopy Theory. We give a brief introduction to topological cyclic homology and the cyclotomic trace map following Nikolaus-Scholze, followed by a proof of B\"okstedt periodicity that closely resembles B\"okstedt's original unpublished proof. We explain the extension of B\"{o}kstedt periodicity by Bhatt-Morrow-Scholze from perfect fields to perfectoid rings and use this to give a purely p-adic proof of Bott periodicity. Finally, we evaluate the cofiber of the assembly map in p-adic topological cyclic homology for the cyclic group of order p and a perfectoid ring of coefficients.

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Lars Hesselholt, Thomas Nikolaus. 2019-05-22. Topological cyclic homology. https://arxiv.org/abs/1905.08984

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