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arXiv · 1211.4141

Quantum Heisenberg models and random loop representations

Daniel Ueltschi
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Abstract

We review random loop representations for the spin-1/2 quantum Heisenberg models, that are due to Toth (ferromagnet) and Aizenman-Nachtergaele (antiferromagnet). These representations can be extended to models that interpolate between the two Heisenberg models, such as the quantum XY model. We discuss the relations between long-range order of the quantum spins and the size of the loops. Finally, we describe conjectures about the joint distribution of the lengths of macroscopic loops, and of symmetry breaking.

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Daniel Ueltschi. 2012-11-17. Quantum Heisenberg models and random loop representations. https://arxiv.org/abs/1211.4141

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