Topological order and topological entropy in classical systems

Claudio Castelnovo; Claudio Chamon; .

doi:10.1103/physrevb.76.174416

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arXiv · cond-mat/0610316

Topological order and topological entropy in classical systems

Claudio Castelnovo·Claudio Chamon·.

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Abstract

We show that the concept of topological order, introduced to describe ordered quantum systems which cannot be classified by broken symmetries, also applies to classical systems. Starting from a specific example, we show how to use pure state density matrices to construct corresponding thermally mixed ones that retain precisely half the original topological entropy, a result that we generalize to a whole class of quantum systems. Finally, we suggest that topological order and topological entropy may be useful in characterizing classical glassy systems.

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Claudio Castelnovo, Claudio Chamon, .. 2007-11-09. Topological order and topological entropy in classical systems. https://doi.org/10.1103/physrevb.76.174416

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