{ "id": "1709.03889", "version": "v1", "published": "2017-09-11T01:03:06.000Z", "updated": "2017-09-11T01:03:06.000Z", "title": "Bilinear forms on Grothendieck groups of triangulated categories", "authors": [ "Peter Webb" ], "comment": "arXiv admin note: substantial text overlap with arXiv:1301.4701", "categories": [ "math.RT" ], "abstract": "We extend the theory of bilinear forms on the Green ring of a finite group developed by Benson and Parker to the context of the Grothendieck group of a triangulated category with Auslander-Reiten triangles, taking only relations given by direct sum decompositions. We examine the non-degeneracy of the bilinear form given by dimensions of homomorphisms, and show that the form may be modified to give a Hermitian form for which the standard basis given by indecomposable objects has a dual basis given by Auslander-Reiten triangles. An application is given to the homotopy category of perfect complexes over a symmetric algebra, with a consequence analogous to a result of Erdmann and Kerner.", "revisions": [ { "version": "v1", "updated": "2017-09-11T01:03:06.000Z" } ], "analyses": { "subjects": [ "16G70", "18E30", "20C20" ], "keywords": [ "bilinear form", "grothendieck group", "triangulated category", "auslander-reiten triangles", "direct sum decompositions" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }