English

KMS states for generalized gauge actions on C*-algebras associated with self-similar sets

Operator Algebras 2021-09-08 v1 Dynamical Systems

Abstract

Given a self-similar KK set defined from an iterated function system Γ=(γ1,,γn)\Gamma=(\gamma_1,\ldots,\gamma_n) and a set of function H={hi:KR}i=1dH=\{h_i:K\to\mathbb{R}\}_{i=1}^d satisfying suitable conditions, we define a generalized gauge action on Kawjiwara-Watatani algebras OΓ\mathcal{O}_\Gamma and their Toeplitz extensions TΓ\mathcal{T}_\Gamma. We then characterize the KMS states for this action. For each β(0,)\beta\in(0,\infty), there is a Ruelle operator LH,β\mathcal{L}_{H,\beta} and the existence of KMS states at inverse temperature β\beta is related to this operator. The critical inverse temperature βc\beta_c is such that LH,βc\mathcal{L}_{H,\beta_c} has spectral radius 1. If β<βc\beta<\beta_c, there are no KMS states on OΓ\mathcal{O}_\Gamma and TΓ\mathcal{T}_\Gamma; if β=βc\beta=\beta_c, there is a unique KMS state on OΓ\mathcal{O}_\Gamma and TΓ\mathcal{T}_\Gamma which is given by the eigenmeasure of LH,βc\mathcal{L}_{H,\beta_c}; and if β>βc\beta>\beta_c, including β=\beta=\infty, the extreme points of the set of KMS states on TΓ\mathcal{T}_\Gamma are parametrized by the elements of KK and on OΓ\mathcal{O}_\Gamma by the set of branched points.

Keywords

Cite

@article{arxiv.2109.03050,
  title  = {KMS states for generalized gauge actions on C*-algebras associated with self-similar sets},
  author = {Gilles G. de Castro},
  journal= {arXiv preprint arXiv:2109.03050},
  year   = {2021}
}