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arXiv · 1405.7429

Entanglement of $π$-LME states and the SAT problem

Adi Makmal·Markus Tiersch·Vedran Dunjko·Shengjun Wu
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Abstract

In this paper we investigate the entanglement properties of the class of $π$-locally maximally entanglable ($π$-LME) states, which are also known as the "real equally weighted states" or the "hypergraph states". The $π$-LME states comprise well-studied classes of quantum states (e.g. graph states) and exhibit a large degree of symmetry. Motivated by the structure of LME states, we show that the capacity to (efficiently) determine if a $π$-LME state is entangled would imply an efficient solution to the boolean satisfiability (SAT) problem. More concretely, we show that this particular problem of entanglement detection, phrased as a decision problem, is $\mathsf{NP}$-complete. The restricted setting we consider yields a technically uninvolved proof, and illustrates that entanglement detection, even when quantum states under consideration are highly restricted, still remains difficult.

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Adi Makmal, Markus Tiersch, Vedran Dunjko, Shengjun Wu. 2014-05-29. Entanglement of $π$-LME states and the SAT problem. https://doi.org/10.1103/physreva.90.042308

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