English

Connections between dynamical systems and crossed products of Banach algebras by $\mathbb{Z}$

Dynamical Systems 2023-05-31 v5

Abstract

Starting with a complex commutative semi-simple regular Banach algebra AA and an automorphism σ\sigma of AA, we form the crossed product of AA with the integers, where the latter act on AA via iterations of σ\sigma. The automorphism induces a topological dynamical system on the character space Δ(A)\Delta(A) of AA in a natural way. We prove an equivalence between the property that every non-zero ideal in the crossed product has non-zero intersection with the subalgebra AA, maximal commutativity of AA in the crossed product, and density of the non-periodic points of the induced system on the character space. We also prove that every non-trivial ideal in the crossed product always intersects the commutant of AA non-trivially. Furthermore, under the assumption that AA is unital and such that Δ(A)\Delta(A) consists of infinitely many points, we show equivalence between simplicity of the crossed product and minimality of the induced system, and between primeness of the crossed product and topological transitivity of the system.

Keywords

Cite

@article{arxiv.math/0702118,
  title  = {Connections between dynamical systems and crossed products of Banach algebras by $\mathbb{Z}$},
  author = {Christian Svensson and Sergei Silvestrov and Marcel de Jeu},
  journal= {arXiv preprint arXiv:math/0702118},
  year   = {2023}
}

Comments

10 pages. Final version