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arXiv · hep-ph/0008040

Quantum Phase Transitions and the Extended Coupled Cluster Method

N. E. Ligterink·N. R. Walet·R. F. Bishop
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Abstract

We discuss the application of an extended version of the coupled cluster method to systems exhibiting a quantum phase transition. We use the lattice O(4) non-linear sigma model in (1+1)- and (3+1)-dimensions as an example. We show how simple predictions get modified, leading to the absence of a phase transition in (1+1) dimensions, and strong indications for a phase transition in (3+1) dimensions.

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N. E. Ligterink, N. R. Walet, R. F. Bishop. 2000-08-04. Quantum Phase Transitions and the Extended Coupled Cluster Method. https://doi.org/10.1103/physreve.63.037103

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