Communication of partial ignorance with qubits

Understand

We introduce a class of communication tests where the task is to communicate partial ignorance by means of a physical system.

• We present a full characterization of the implementations of these tests in the qubit case and partial results for qudits.
• A peculiar observation is that two physical systems with the same operational dimensions may differ with respect to implementations of these tasks, as is shown to be the case for the qubit and rebit.
• Finally, we consider the natural question whether some of the communication tests are more difficult than others.