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arXiv · 2202.03127

Genuine Activation of Quantum Nonlocality: Stronger Than Local Indistinguishability

Tathagata Gupta·Subhendu B. Ghosh·Ardra A V·Anandamay Das Bhowmik·Sutapa Saha·Tamal Guha·Ramij Rahaman·Amit Mukherjee
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Abstract

The structure of quantum theory assures the discrimination of any possible orthogonal set of states. However, the scenario becomes highly nontrivial in the limited measurement setting and leads to different classes of impossibility, viz., indistinguishability, unmarkability, irreducibility etc. These phenomena, often referred to as other nonlocal aspects of quantum theory, have utmost importance in the domain of secret sharing etc. It, therefore, becomes a pertinent question to distill/activate such behaviours from a set, apparently devoid of these nonlocal features and free from local redundancy. While the activation of local indisitinguishability in the sets of entangled states has recently been reported, other stronger notion of quantum nonlocality has yet not been inspected in the parlance of activation. Here, we explored all such stronger versions of nonlocality and affirmatively answered to activate each of them. We also find a locally distinguishable set of multipartite entangled states which can be converted with certainty to a nontrivial set of locally irreducible genuinely entangled states.

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Tathagata Gupta, Subhendu B. Ghosh, Ardra A V, Anandamay Das Bhowmik, Sutapa Saha, Tamal Guha, Ramij Rahaman, Amit Mukherjee. 2022-02-07. Genuine Activation of Quantum Nonlocality: Stronger Than Local Indistinguishability. https://doi.org/10.1103/physreva.107.052418

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