Jesús M. F. Castillo

activity

20222025

collaborators

4 papers

math.FA2025

Derived functors associated to the ideal of compact operators in Banach spaces

Félix Cabello Sánchez, Jesús M. F. Castillo, Alberto Salguero-Alarcón +1

We compute the derived functors of (the functors associated to) the ideal of compact operators in Banach spaces and obtain new results about the extension and lifting of compact op…

math.FA2025

Polyhedrality for twisted sums with $C (ω^{α})$

Jesús M. F. Castillo, Alberto Salguero Alarcón

We obtain two partial answers to the 3-space problem for isomorphic polyhedrality: (1) every twisted sum of $C (α)$ , $α < ω_{1}$ , with a separable isomorphically polyhedral space with t…

math.FA2024

Trimming the Johnson bonsai

Félix Cabello Sánchez, Jesús M. F. Castillo, Yolanda Moreno

We show that if $p > 1$ every subspace of $ℓ_{p} (Γ)$ is an $ℓ_{p}$ -sum of separable subspaces of $ℓ_{p}$ , and we provide examples of subspaces of $ℓ_{p} (Γ)$ for $0 < p \leq 1$ that…

math.FA2022

Twisted sums of $c_{0} (I)$

Jesús M. F. Castillo, Alberto Salguero Alarcón

The paper studies properties of twisted sums of a Banach space $X$ with $c_{0} (κ)$ . We first prove a representation theorem for such twisted sums from which we will obtain, among oth…

Derived functors associated to the ideal of compact operators in Banach spaces

Polyhedrality for twisted sums with C(ωα)

Trimming the Johnson bonsai

Twisted sums of c0​(I)

Polyhedrality for twisted sums with $C (ω^{α})$

Twisted sums of $c_{0} (I)$