The closed subgroup problem for lattice-ordered groups
Kenoyer gave two examples proving that in the lattice of convex \(\ell\)- subgroups of a lattice-ordered group it was impossible to distinguish the closed convex \(\ell\)-subgroups. However, one of his examples was non- normal-valued. Here the same question is recast for normal-valued \(\ell\)- groups, and it remains open. The main theorem gives an interesting class of \(\ell\)-groups in which closed convex \(\ell\)-subgroups can be recognized in the lattice of convex \(\ell\)-subgroups.
scientific article; zbMATH DE number 4116602
scientific article