1210.1689 (Salman Beigi)

A New Quantum Data Processing Inequality    [PDF]

Salman Beigi

Quantum data processing inequality bounds the set of bipartite states that can be generated by two far apart parties under local operations; Having access to a bipartite state as a resource, two parties cannot locally transform it to another bipartite state with a mutual information greater than that of the resource state. But due to the additivity of quantum mutual information under tensor product, data processing inequality gives no bound when the parties are provided with infinitely many copies of the resource state. In this paper we introduce a measure of correlation on bipartite quantum states that is not additive and gives the same number when computed for multiple copies. Then by proving a data processing inequality for this measure, we find a bound on the set of states that can be generated under local operations even when an infinite number of copies of the resource state is available. We show that this measure fully characterizes bipartite states from which common randomness can be distilled under local operations.

View original: http://arxiv.org/abs/1210.1689