2004/03/19 by Vladimir Peller, Peller, Vladimir
Mathematics · #46E35 #47A55 #47A63 #47B10 #Classical Analysis and ODEs (math.CA) #Complex Variables (math.CV) #FOS: Mathematics #Functional Analysis (math.FA) #math.CA #math.CV #math.FA #msc:46E35 #msc:47A55 #msc:47A63 #msc:47B10
paper · pdf · doi:10.48550/arxiv.math/0403327
21 pages
arxiv created 2004/03/19 · arxiv updated 2009/12/01
Koplienko [Ko] found a trace formula for perturbations of self-adjoint operators by operators of Hilbert Schmidt class \bS2. A similar formula in the case of unitary operators was obtained by Neidhardt [N]. In this paper we improve their results and obtain sharp conditions under which the Koplienko--Neidhardt trace formulae hold.