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arXiv · 1503.07083

Complexity of the XY antiferromagnet at fixed magnetization

Andrew M. Childs·David Gosset·Zak Webb
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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.

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Andrew M. Childs, David Gosset, Zak Webb. 2015-10-19. Complexity of the XY antiferromagnet at fixed magnetization. https://doi.org/10.26421/qic16.1-2

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