Ahmed Younis

Quantitative Signalling-to-Product Rigidity for Two-Qubit Unitary Channels

For a bipartite unitary channel, exact absence of one-way signalling is known to force product structure. We give an explicit quantitative version for two-qubit unitaries. Let Sigma_{A->B}(U) be the unhalved diamond-norm distance of Bob's reduced output channel from the set of ch...

Quantitative Signalling-to-Product Rigidity for Two-Qubit Unitary Channels

For a bipartite unitary channel, exact absence of one-way signalling is known to force product structure. We give an explicit quantitative version for two-qubit unitaries. Let Sigma_{A->B}(U) be the unhalved diamond-norm distance of Bob's reduced output channel from the set of ch...