English

Quantum Spin probabilities at positive temperature are H\"older Gibbs probabilities

Dynamical Systems 2018-05-17 v2 Statistical Mechanics Mathematical Physics math.MP Quantum Physics

Abstract

We consider the KMS state associated to the Hamiltonian H=σxσxH= \sigma^x \otimes \sigma^x over the quantum spin lattice C2C2C2...\mathbb{C}^2 \otimes \mathbb{C}^2 \otimes \mathbb{C}^2 \otimes .... For a fixed observable of the form LLL...L \otimes L \otimes L \otimes ..., where L:C2C2L:\mathbb{C}^2 \to \mathbb{C}^2 is self adjoint, and for positive temperature TT one can get a naturally defined stationary probability μT\mu_T on the Bernoulli space {1,2}N\{1,2\}^\mathbb{N}. The Jacobian of μT\mu_T can be expressed via a certain continued fraction expansion. We will show that this probability is a Gibbs probability for a H\"older potential. Therefore, this probability is mixing for the shift map. For such probability μT\mu_T we will show the explicit deviation function for a certain class of functions. When decreasing temperature we will be able to exhibit the explicit transition value TcT_c where the set of values of the Jacobian of the Gibbs probability μT\mu_T changes from being a Cantor set to being an interval. We also present some properties for quantum spin probabilities at zero temperature (for instance, the explicit value of the entropy).

Cite

@article{arxiv.1805.01784,
  title  = {Quantum Spin probabilities at positive temperature are H\"older Gibbs probabilities},
  author = {Jader E. Brasil and Artur O. Lopes and Jairo K. Mengue and Carlos G. Moreira},
  journal= {arXiv preprint arXiv:1805.01784},
  year   = {2018}
}
R2 v1 2026-06-23T01:45:17.504Z