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arXiv · 0711.1344

Entanglement of subspaces in terms of entanglement of superpositions

Gilad Gour·Aidan Roy
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Abstract

We investigate upper and lower bounds on the entropy of entanglement of a superposition of bipartite states as a function of the individual states in the superposition. In particular, we extend the results in [G. Gour, arxiv.org:0704.1521 (2007)] to superpositions of several states rather than just two. We then investigate the entanglement in a subspace as a function of its basis states: we find upper bounds for the largest entanglement in a subspace and demonstrate that no such lower bound for the smallest entanglement exists. Finally, we consider entanglement of superpositions using measures of entanglement other than the entropy of entanglement.

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Gilad Gour, Aidan Roy. 2007-11-08. Entanglement of subspaces in terms of entanglement of superpositions. https://doi.org/10.1103/physreva.77.012336

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