# Bipartite subspaces having no LOCC-distinguishable bases

@inproceedings{Watrous2005BipartiteSH,
title={Bipartite subspaces having no LOCC-distinguishable bases},
author={John Watrous},
year={2005}
}
It is proved that there exist subspaces of bipartite tensor product spaces that have no or-thonormal bases that can be perfectly distinguished by means of LOCC protocols. A corollary of this fact is that there exist quantum channels having sub-optimal classical capacity even when the receiver may communicate classically with a third party that represents the channel's environment.
9 Citations
Reliably distinguishing states in qutrit channels using one-way LOCC
• Computer Science
• 2005
We present numerical evidence showing that any three-dimensional subspace of C^3 \otimes C^n has an orthonormal basis which can be reliably distinguished using one-way LOCC, where a measurement is
Quantum nonlocality without entanglement: explicit dependence on prior probabilities of nonorthogonal mirror-symmetric states
• Physics
• 2021
In the case of a multi-party system, through local operations and classical communication (LOCC), each party may not perform perfect discrimination of quantum states that are separable and
Using entanglement more efficiently in distinguishing orthogonal product states by LOCC
• Physics
Quantum Inf. Process.
• 2019
This paper presents a method to locally distinguish a set of $$2n-1$$ orthogonal product states in a $$m \otimes n$$ bipartite system with an ancillary two-qubit maximally entangled state, and generalize the discrimination method to Orthogonal Product states in even-partite system.
Quantum nonlocality without entanglement depending on nonzero prior probabilities in optimal unambiguous discrimination
• Physics
Scientific reports
• 2021
It is shown that even in optimal unambiguous discrimination, the occurrence of NLWE can depend on nonzero prior probabilities, and the results provide new insights into classifying sets of multipartite quantum states in terms of quantum state discrimination.
Nonlocality of tripartite orthogonal product states
• Mathematics
Quantum Inf. Process.
• 2021
It is proved that a three-qubit GHZ state is sufficient as a resource to distinguish each of the above classes of states.
Strong quantum nonlocality for multipartite entangled states
• Physics
Quantum Inf. Process.
• 2021
A general definition of strong quantum nonlocality based on the local indistinguishability is presented and it is shown that a set of orthogonal entangled states is locally reducible but locally indistinguishable in all bipartitions, which means the states have strong nonLocality.

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