2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/112665We show that compact cardinals and {\rm MM} are sensitive to $λ$-closed forcings for arbitrarily large $λ$. This is done by adding 'regressive' $λ$-Kurepa-trees in either case. We argue that the destruction of regressive Kurepa-trees with {\rm MM} requires the use of Namba forcing.Logictext