Loop spaces of $n$-dimensional Poincaré duality complexes whose $(n-1)$-skeleton is a co-$H$-space

Abstract: Under certain hypotheses, we prove a loop space decomposition for simply-connected Poincar\'e Duality complexes of dimension $n$ whose $(n-1)$-skeleton is a co-$H$-space. This unifies many known decompositions obtained in different contexts and establishes many new families of examples. As consequences, we show that such a looped Poincar\'{e} Duality complex retracts off the loops of its $(n-1)$-skeleton and describe its homology as a one-relator algebra.