English

Transfinite almost square Banach spaces

Functional Analysis 2022-04-29 v1

Abstract

It is known that a Banach space contains an isomorphic copy of c0c_0 if, and only if, it can be equivalently renormed to be almost square. We introduce and study transfinite versions of almost square Banach spaces with the purpose to relate them to the containment of isomorphic copies of c0(κ)c_0(\kappa), where κ\kappa is some uncountable cardinal. We also provide several examples and stability results of the above properties by taking direct sums, tensor products and ultraproducts. By connecting the above properties with transfinite analogues of the strong diameter two property and octahedral norms, we obtain a solution to an open question from [8].

Keywords

Cite

@article{arxiv.2204.13449,
  title  = {Transfinite almost square Banach spaces},
  author = {Antonio Avilés and Stefano Ciaci and Johann Langemets and Aleksei Lissitsin and Abraham Rueda Zoca},
  journal= {arXiv preprint arXiv:2204.13449},
  year   = {2022}
}

Comments

23 Pages

R2 v1 2026-06-24T11:01:25.400Z