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N-representability is QMA-complete

Y. -K. Liu·M. Christandl·F. Verstraete
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Abstract

We study the computational complexity of the N-representability problem in quantum chemistry. We show that this problem is QMA-complete, which is the quantum generalization of NP-complete. Our proof uses a simple mapping from spin systems to fermionic systems, as well as a convex optimization technique that reduces the problem of finding ground states to N-representability.

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Y. -K. Liu, M. Christandl, F. Verstraete. 2006-09-17. N-representability is QMA-complete. https://doi.org/10.1103/physrevlett.98.110503

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