Higher order S2-differentiability and application to Koplienko trace formula

Autor: Anna Skripka, Christian Le Merdy, Clément Coine, Fedor Sukochev
Rok vydání: 2019
Předmět:
Zdroj: Journal of Functional Analysis. 276:3170-3204
ISSN: 0022-1236
DOI: 10.1016/j.jfa.2018.09.005
Popis: Let A be a selfadjoint operator in a separable Hilbert space, K a selfadjoint Hilbert–Schmidt operator, and f ∈ C n ( R ) . We establish that φ ( t ) = f ( A + t K ) − f ( A ) is n-times continuously differentiable on R in the Hilbert–Schmidt norm, provided either A is bounded or the derivatives f ( i ) , i = 1 , … , n , are bounded. This substantially extends the results of [3] on higher order differentiability of φ in the Hilbert–Schmidt norm for f in a certain Wiener class. As an application of the second order S 2 -differentiability, we extend the Koplienko trace formula from the Besov class B ∞ 1 2 ( R ) [20] to functions f for which the divided difference f [ 2 ] admits a certain Hilbert space factorization.
Databáze: OpenAIRE