activity
20212026
collaborators

6 papers

math.OA2026

Complexity Rank of AT Algebras of Real Rank Zero

Qingnan An, Kang Li, Zhichao Liu

In this paper, we prove that every separable unital AT algebra of real rank zero has complexity rank at most one. In particular, every irrational rotation algebra has complexity ra…

math.FA2023

Integral operators in the spaces of functions of bounded Schramm variation

Jacek Gulgowski, Piotr Kasprzak, Piotr Maćkowiak

In this paper we provide a full characterization of linear integral operators acting from the space of functions of bounded Jordan variation to the space of functions of bounded Sc…

math.FA2023

Properties of local orthonormal systems, Part II: Geometric characterization of Bernstein inequalities

Jacek Gulgowski, Anna Kamont, Markus Passenbrunner

Let be a probability space and let be a binary filtration, i.e. exactly one atom of is divided into two atoms of $\m…

math.FA2023

Properties of local orthonormal systems, Part I: Unconditionality in

Jacek Gulgowski, Anna Kamont, Markus Passenbrunner

Assume that we are given a filtration on a probability space of the form that each is generated by the partition of one a…

math.FA2022

Compactness in Lipschitz spaces and around

Jacek Gulgowski, Piotr Kasprzak, Piotr Maćkowiak

The aim of the paper is to characterize (pre)compactness in the spaces of Lipschitz/Hölder continuous mappings acting from a compact metric space to a normed space. To this end som…

math.FA2021

Compactness in normed spaces: a unified approach through semi-norms

Jacek Gulgowski, Piotr Kasprzak, Piotr Maćkowiak

In this paper we prove two new abstract compactness criteria in normed spaces. To this end we first introduce the notion of an equinormed set using a suitable family of semi-norms…