A new operator extension of strong subadditivity of quantum entropy

Ting-Chun Lin, Isaac H. Kim, Min-Hsiu Hsieh

Let $S(\rho )$ be the von Neumann entropy of a density matrix $\rho$. Weak monotonicity asserts that $S({\rho }_{AB})-S({\rho }_A)+S({\rho }_{BC})-S({\rho }_C)\ge 0$ for any tripartite density matrix $ρ_{…