A quantum state represents neither properties of a physical system nor anyone’s knowledge of its properties. The important question is not what quantum states represent but how they are used—as informational bridges. Knowing about some physical situations (its backing conditions), an agent may assign a quantum state to form expectations about other possible physical situations (its advice conditions). Quantum states are objective: only expectations based on correct state assignments are generally reliable. If a quantum state represents anything, it is the objective probabilistic relations between its backing conditions and its advice conditions. This paper offers an account of quantum states and their function as informational bridges, in quantum teleportation and elsewhere.
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But doesn’t Carol herself provide such a physical channel? Not if all traces of what she did have been erased from her brain and the rest of her body.
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Healey, R. Quantum States as Objective Informational Bridges. Found Phys 47, 161–173 (2017). https://doi.org/10.1007/s10701-015-9949-7
- Quantum state
- Quantum information
- Quantum teleportation
- Delayed-choice entanglement-swapping
- EPR-Bohm correlations