Maximally nonlocal subspaces

Akshata Shenoy H.; R. Srikanth

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arXiv · 1802.05585

Maximally nonlocal subspaces

Akshata Shenoy H.·R. Srikanth

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Abstract

A nonlocal subspace $\mathcal{H}_{NS}$ is a subspace within the Hilbert space $\mathcal{H}_n$ of a multi-particle system such that every state $\psi \in \mathcal{H}_{NS}$ violates a given Bell inequality $\mathcal{B}$. Subspace $\mathcal{H}_{NS}$ is maximally nonlocal if each such state $\psi$ violates $\mathcal{B}$ to its algebraic maximum. We propose ways by which states with a stabilizer structure of graph states can be used to construct maximally nonlocal subspaces, essentially as a degenerate eigenspace of Bell operators derived from the stabilizer generators. Two cryptographic applications-- to quantum information splitting and quantum subspace certification-- are discussed.

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BibTeX RIS

Akshata Shenoy H., R. Srikanth. 2018-02-15. Maximally nonlocal subspaces. https://arxiv.org/abs/1802.05585

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