



@article {1234,
	title = {Complexity of the XY antiferromagnet at fixed magnetization},
	journal = {Quantum Information and Computation},
	volume = {16},
	year = {2016},
	month = {2016/01/01},
	pages = {1-18},
	abstract = {  We prove that approximating the ground energy of the antiferromagnetic XY
model on a simple graph at fixed magnetization (given as part of the instance
specification) is QMA-complete. To show this, we strengthen a previous result
by establishing QMA-completeness for approximating the ground energy of the
Bose-Hubbard model on simple graphs. Using a connection between the XY and
Bose-Hubbard models that we exploited in previous work, this establishes
QMA-completeness of the XY model.
},
	url = {http://arxiv.org/abs/1503.07083v1},
	author = {Andrew M. Childs and David Gosset and Zak Webb}
}
