2 papers
math.FA2022
Left-invertibility of rank-one perturbations
Susmita Das, Jaydeb Sarkar
For each isometry acting on some Hilbert space and a pair of vectors and in the same Hilbert space, we associate a nonnegative number defined by \[ c(V; f,g)…
math.FA2021
Invariant subspaces of analytic perturbations
Susmita Das, Jaydeb Sarkar
By analytic perturbations, we refer to shifts that are finite rank perturbations of the form , where is the unilateral shift and is a finite rank operator on the…