# Characterizing entanglement via uncertainty relations.

@article{Ghne2004CharacterizingEV, title={Characterizing entanglement via uncertainty relations.}, author={Otfried G{\"u}hne}, journal={Physical review letters}, year={2004}, volume={92 11}, pages={ 117903 } }

We derive a family of necessary separability criteria for finite-dimensional systems based on inequalities for variances of observables. We show that every pure bipartite entangled state violates some of these inequalities. Furthermore, a family of bound entangled states and true multipartite entangled states can be detected. The inequalities also allow us to distinguish between different classes of true tripartite entanglement for qubits. We formulate an equivalent criterion in terms of…

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