@article {1588, title = {N-representability is QMA-complete}, journal = {Phys. Rev. Lett.}, volume = {98}, year = {2007}, month = {2007/03/16}, abstract = {We study the computational complexity of the N-representability problem in quantum chemistry. We show that this problem is quantum Merlin-Arthur complete, which is the quantum generalization of nondeterministic polynomial time 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.}, doi = {10.1103/PhysRevLett.98.110503}, url = {http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.98.110503}, author = {Yi-Kai Liu and Matthias Christandl and F. Verstraete} }