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arXiv · 1501.06612

$THH$ and base-change for Galois extensions of ring spectra

Akhil Mathew
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Abstract

We treat the question of base-change in $THH$ for faithful Galois extensions of ring spectra in the sense of Rognes. Given a faithful Galois extension $A \to B$ of ring spectra, we consider whether the map $THH(A) \otimes_A B \to THH(B)$ is an equivalence. We reprove and extend positive results of Weibel-Geller and McCarthy-Minasian and offer new examples of Galois extensions for which base-change holds. We also provide a counterexample where base-change fails.

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BibTeXRIS

Akhil Mathew. 2016-07-18. $THH$ and base-change for Galois extensions of ring spectra. https://doi.org/10.2140/agt.2017.17.693

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