On decomposability of positive maps between $M_2$ and $M

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/103579A map $ϕ:M_m(\bC)\to M_n(\bC)$ is decomposable if it is of the form $ϕ=ϕ_1+ϕ_2$ where $ϕ_1$ is a CP map while $ϕ_2$ is a co-CP map. A partial characterization of decomposability for maps $ϕ: M_2(\bC) \to M_3(\bC)$ is given.7 pagesFunctional AnalysisOperator Algebras47B65, 47L07On decomposability of positive maps between $M_2$ and $M_n$text