Abstract How reasonable is the conjecture that _ /C0, 1 ℓ ∞ / C 0, 1 separably injective? Formulated in homological terms this amounts to asking whether Ext² (S, C0, 1) =0 Ext 2 (S, C 0, 1) = 0 for every separable space. We wheel around this question and obtain new connections between Ext² Ext 2 -results and classical Banach space theorems of Johnson–Zippin, Kalton and Lindenstrauss–Pełczyński.
Castillo et al. (Sun,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: