Henrik Wirzenius

activity

20182025

most citedClosed ideals in the algebra of compact-by-approximable operators

4 citations · 10 across the 7 of their papers we have counts for

collaborators

7 papers

math.FA2025

Structure of closed subideals of $L (X)$

Hans-Olav Tylli, Henrik Wirzenius

The closed subalgebra $J$ of the Banach algebra $L (X)$ of bounded linear operators on the Banach space $X$ is a non-trivial closed $I$ -subideal of $\math…

math.FA2025

Compactness of compositions of strictly singular operators on direct sums of Baernstein, Schreier and $ℓ_{p}$ -spaces

Niels Jakob Laustsen, Henrik Wirzenius

Let $X$ be the direct sum of finitely many Banach spaces chosen from the following three families: (i) the Baernstein spaces $B_{p}$ for $1 < p < \infty$ ; (ii) the $p$ -convexified Schrei…

math.FA2023

Exotic closed subideals of algebras of bounded operators

Hans-Olav Tylli, Henrik Wirzenius

We exhibit a Banach space $Z$ failing the approximation property, for which there is an uncountable family $F$ of closed subideals contained in the Banach algebra $\mathca…

math.FA2022★ 1 cited

On approximation properties related to unconditionally p-compact operators and Sinha-Karn p-compact operators

Henrik Wirzenius

We establish new results on the $I$ -approximation property for the Banach operator ideal $I = K_{u p}$ of the unconditionally $p$ -compact operators in the…

math.FA2022★ 2 cited

Quotient algebras of Banach operator ideals related to non-classical approximation properties

Henrik Wirzenius

We investigate the quotient algebra $A_{X}^{I} := I (X) / F (X)^{∣∣ \cdot ∣ ∣_{I}}$ for Banach operator ideals $I$ contained…

math.FA2021★ 4 cited

Closed ideals in the algebra of compact-by-approximable operators

Hans-Olav Tylli, Henrik Wirzenius

We construct various examples of non-trivial closed ideals of the compact-by-approximable algebra $A_{X} =: K (X) / A (X)$ on Banach spaces $X$ failing the ap…

math.FA2018★ 3 cited

Quotient algebra of compact-by-approximable operators on Banach spaces failing the approximation property

Hans-Olav Tylli, Henrik Wirzenius

We initiate a study of structural properties of the quotient algebra $K (X) / A (X)$ of the compact-by-approximable operators on Banach spaces $X$ failing the approxi…

Structure of closed subideals of L(X)

Compactness of compositions of strictly singular operators on direct sums of Baernstein, Schreier and ℓp​-spaces

Exotic closed subideals of algebras of bounded operators

On approximation properties related to unconditionally p-compact operators and Sinha-Karn p-compact operators

Quotient algebras of Banach operator ideals related to non-classical approximation properties

Closed ideals in the algebra of compact-by-approximable operators

Quotient algebra of compact-by-approximable operators on Banach spaces failing the approximation property

Structure of closed subideals of $L (X)$

Compactness of compositions of strictly singular operators on direct sums of Baernstein, Schreier and $ℓ_{p}$ -spaces