Equality of maximal deflation-exact structures on complete LB-spaces

Determine whether, on the category LB of complete LB-spaces, the maximal (strongly) deflation-exact structure D equals the restriction D \cap LB of the maximal deflation-exact structure on all LB-spaces; equivalently, decide whether in the description of D one may replace “semistable” with “surjective.”

Background

The authors show inclusion D \subseteq D \cap LB for the maximal deflation-exact structure, with semistable cokernels playing a central role. Whether equality holds (i.e., surjective implies semistable in this setting) would impact the characterization of conflations and acyclic complexes in the complete LB category.

References

It is unknown if in Theorem \ref{LBc-Defl} equality holds, that is, if, in the description of $D$, one may replace ‘semistable’ with ‘surjective’ or not.

A homological approach to (Grothendieck's) completeness problem for regular LB-spaces  (2512.13161 - Wegner, 15 Dec 2025) in Section “Complete LB-spaces” (SEC-COM), after Theorem LBc-Defl, final remarks