Operator Differentiable Functions
Operator Differentiable Functions
We study the Banach \*-algebra \_C\_1QP(I) of \_C\_1-functions on the compact interval I such that the corresponding Hilbert space operator function T → f(T), for T = T\* and sp(T) ⊂ I, is Fréchet differentiable. If f(x) = ∫ eitx f^(t)dt we know that the differential is given by the …