3 papers
math.FA2021
On perturbations of woven pairs of frames
Pablo Calderón, Mariano Ruiz
In this note, we prove some results related to small perturbations of a frame for a Hilbert space in order to have a woven pair for . Our results complet…
math.FA2020
Local extrema for Procustes problems in the set of positive definite matrices
Pablo Calderón, Noelia B. Rios, Mariano A. Ruiz
Given two positive definite matrices and , a well known result by Gelfand, Naimark and Lidskii establishes a relationship between the eigenvalues of and and those of…
math.FA2017
A note on perturbations of Fusion Frames
M. Ruiz, P. Calderón
In this work, we consider some relationships between a closed range operator and a fusion frame for a Hilbert space that provides…