A combinatorial principle equivalent to the existence of non-free Whitehead groups

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/152898As a consequence of identifying the principle described in the title, we prove that for any uncountable cardinal lambda, if there is a lambda-free Whitehead group of cardinality lambda which is not free, then there are many ``nice'' Whitehead groups of cardinality lambda which are not free.LogicRings and AlgebrasA combinatorial principle equivalent to the existence of non-free Whitehead groupstext