Characterization of the $\sigma$-Dedekind complete Riesz space by the subadditivity of its positive part mapping

A. B. Németh

Two retractions $M$ and $N$ on convex cones $\mathbf{M}$ and respectively $\mathbf{N}$ of a real vector space $X$ are called mutually polar if $M+N=I$ and $MN=NM=0.$ In this note it is shown…