{ "id": "2104.08864", "version": "v1", "published": "2021-04-18T14:17:07.000Z", "updated": "2021-04-18T14:17:07.000Z", "title": "Koplienko trace formula for unitaries via linear path", "authors": [ "Arup Chattopadhyay", "Soma Das", "Chandan Pradhan" ], "comment": "24 pages, Submitted to Journal. arXiv admin note: text overlap with arXiv:2010.04039", "categories": [ "math.FA" ], "abstract": "Koplienko \\cite{Ko} found a trace formula for perturbations of self-adjoint operators by operators of Hilbert-Schmidt class $\\mathcal{B}_2(\\mathcal{H})$. In 2012, Potapov and Sukochev \\cite{PoSu} obtained a similar formula for pairs of contractions by answering an open question posed by Gesztesy, Pushnitski, and Simon in \\cite[Open Question 11.2]{GePu}. In this article, we give a still another proof of the Koplienko trace formula in the case of unitary operators via linear path by reducing the problem to a finite-dimensional one as in the proof of Krein's trace formula by Voiculescu \\cite{Voi}, Sinha and Mohapatra \\cite{MoSi94,MoSi96}. Consequently, we obtain the Koplienko trace formula for a class of pairs of contractions using the Sch$\\ddot{a}$ffer matrix unitary dilation. Moreover, we also obtain the Koplienko trace formula for a pair of self-adjoint operators and maximal dissipative operators using the Cayley transform.", "revisions": [ { "version": "v1", "updated": "2021-04-18T14:17:07.000Z" } ], "analyses": { "subjects": [ "47A55", "47A56", "47A13", "47B10" ], "keywords": [ "koplienko trace formula", "linear path", "ffer matrix unitary dilation", "self-adjoint operators", "kreins trace formula" ], "note": { "typesetting": "TeX", "pages": 24, "language": "en", "license": "arXiv", "status": "editable" } } }