Time Symmetry in Operational Theories

Understand

The standard operational probabilistic framework (within which we can formulate Operational Quantum Theory) is time asymmetric.

• This is clear because the conditions on allowed operations are time asymmetric.
• It is odd, though, because Schoedinger's equation is time symmetric and probability theory does not care about time direction.
• In this work we provide a time symmetric framework for operational theories in general and for Quantum Theory in particular.