Krein’s Trace Formula for Unitary Operators and Operator Lipschitz Functions
نویسندگان
چکیده
The spectral shift function for pairs of selfadjoint operators was introduced in the paper by I.M. Lifshits [17]. In the same paper a trace formula for the difference of functions of the perturbed operator and the unperturbed operator was established. Ideas by Lifshits were developed in the paper by M.G. Krein [14], in which the spectral shift function ξ in L1(R) was defined for arbitrary pairs of self-adjoint operators A and B with A − B in trace class, and the Lifshits trace formula
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