Local Discrimination of Quantum Measurement without Assistance of Classical Information

Abstract

The discrimination of quantum operations is an important subject of quantum information processes. For the local distinction, existing researches pointed out that, since any operation performed on a quantum system must be compatible with no-signaling constraint, local discrimination between quantum operations of two spacelike separated parties cannot be realized. We found that, however, local discrimination of quantum measurements may be not restricted by the nosignaling if more multi-qubit entanglement and selective measurements were employed. In this paper, we report that local quantum measurement discrimination (LQMD) can be completed via selective projective measurements and numerous seven-qubit GHZ states without help of classical communication if both two observers agreed in advance that one of them should measure her/his qubits before an appointed time. As an application, it is shown that the teleportation can be completed via the LQMD without classical information. This means that the superluminal communication can be realized by using the LQMD.