Mark Carney

Tracing the Loop: Non-Causal Computation, Partial Traces,&Postselected Entanglement

This paper gives a categorical interpretation of Baumeler \&Wolf's logically consistent non-causal circuits, connecting them to postselected quantum teleportation. Looped feedback is represented by a trace in the category of non-negative matrices, and it is shown that the traced process is stochastic precisely when the...