{ "id": "2309.11463", "version": "v1", "published": "2023-09-20T17:00:13.000Z", "updated": "2023-09-20T17:00:13.000Z", "title": "Algebraic K-theory of real topological K-theory", "authors": [ "Gabriel Angelini-Knoll", "Christian Ausoni", "John Rognes" ], "comment": "48 pages. Comments welcome", "categories": [ "math.AT", "math.KT" ], "abstract": "We calculate the A(1)-homotopy of the topological cyclic homology of the connective real topological K-theory spectrum ko, and show that it is a finitely generated and free F_2[v_2^{32}]-module of even rank between 390 and 444, on explicit generators in stems -1 \\le *\\le 198. This is achieved by using syntomic cohomology of ko as introduced by Hahn-Raksit-Wilson, extending work of Bhatt-Morrow-Scholze from the case of classical rings to E_\\infty rings. In our case there are nontrivial differentials in the motivic spectral sequence from syntomic cohomology to topological cyclic homology, unlike in the case of complex K-theory at odd primes that was studied by Hahn-Raksit-Wilson.", "revisions": [ { "version": "v1", "updated": "2023-09-20T17:00:13.000Z" } ], "analyses": { "subjects": [ "19D50", "19D55", "55Q51", "55P43", "14F30", "19E20", "13D03", "55N15", "55Q10", "55T25" ], "keywords": [ "algebraic k-theory", "topological cyclic homology", "real topological k-theory spectrum ko", "syntomic cohomology", "connective real topological k-theory spectrum" ], "note": { "typesetting": "TeX", "pages": 48, "language": "en", "license": "arXiv", "status": "editable" } } }