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arXiv · 1604.05857

Towards an understanding of ramified extensions of structured ring spectra

Bjørn Ian Dundas·Ayelet Lindenstrauss·Birgit Richter
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Abstract

We propose topological Hochschild homology as a tool for measuring ramification of maps of structured ring spectra. We determine second order topological Hochschild homology of the $p$-local integers. For the tamely ramified extension of the map from the connective Adams summand to $p$-local complex topological K-theory we determine the relative topological Hochschild homology and show that it detects the tame ramification of this extension. We also determine relative topological Hochschild homology for the complexification map from connective real to complex topological K-theory and for some quotient maps with commutative quotients.

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Bjørn Ian Dundas, Ayelet Lindenstrauss, Birgit Richter. 2016-04-20. Towards an understanding of ramified extensions of structured ring spectra. https://doi.org/10.1017/s0305004118000099

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