Complexity of the XY antiferromagnet at fixed magnetization

نویسندگان

  • Andrew M. Childs
  • David Gosset
  • Zak Webb
چکیده

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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عنوان ژورنال:
  • Quantum Information & Computation

دوره 16  شماره 

صفحات  -

تاریخ انتشار 2016