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arXiv · 1510.07513

Phase transition in O_2

Klaus Thomsen
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Abstract

We exhibit a one-parameter group of automorphism on the Cuntz-algebra O_2 such that the simplex of KMS states changes abruptly at a certain critical temperature from infinitely many to one, and then none. The factor types of the extremal KMS states are also determined.

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Klaus Thomsen. 2015-11-04. Phase transition in O_2. https://doi.org/10.1007/s00220-016-2742-4

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