Representations of ideals in Polish groups and in Banach spaces
Abstract
We investigate ideals of the form is unconditionally convergent , where is a sequence in a Polish group or in a Banach space. If an ideal on can be seen in this form for some sequence in , then we say that it is representable in . After numerous examples we show the following theorems: (1) An ideal is representable in a Polish Abelian group iff it is an analytic P-ideal. (2) An ideal is representable in a Banach space iff it is a non-pathological analytic P-ideal. We focus on the family of ideals representable in . We prove that the trace of the null ideal, Farah's ideal, and Tsirelson ideals are not representable in , and that a tall P-ideal is representable in iff it is a summable ideal. Also, we provide an example of a peculiar ideal which is representable in but not in . Finally, we summarize some open problems of this topic.
Keywords
Cite
@article{arxiv.1402.0441,
title = {Representations of ideals in Polish groups and in Banach spaces},
author = {Piotr Borodulin-Nadzieja and Barnabas Farkas and Grzegorz Plebanek},
journal= {arXiv preprint arXiv:1402.0441},
year = {2014}
}