Problem 35

Ergodic non hyperbolic automorphisms of $\mathbb{T}^n$. Are they quotients of subshifts of finite type? Do they satisfy specification?

Comments

  • Ledrappier (2016-11-14 13:51:34 -0800 -0800):

    Not really; cf [lind1982dynamical]

  • BrianMarcus (2016-11-17 22:05:00 -0800 -0800):
  • Anthonyquas (2016-12-01 22:09:27 -0800 -0800):

    Lemma 2.1 of this paper shows a specification-like property provided the gaps between specified blocks grow sub-linearly in the lengths of the orbit segments that are being constrained. (For ordinary specification, these gaps are of constant length).

  • Mike Boyle (2017-07-27 16:33:30 -0700 -0700):

    The ergodic nonhyperbolic toral automorphisms do not admit covers by shifts of finite type, but there are other symbolic representations. See [LindenstraussSchmidt2005] .

  • Douglas Lind (2017-07-29 07:34:00 -0700 -0700):

    The state of the art in symbolic representations of toral automorphisms is contained in the paper Representations of toral automorphisms by Klaus Schmidt, Topology and its applications 205 (2016), 88-116 [SchmidtToral] .

  • Douglas Lind (2017-07-30 08:00:46 -0700 -0700):

    A complete description of the specification properties of ergodic toral automorphisms is given in “Ergodic group automorphisms and specification”, Douglas Lind, Springer Lecture Notes in Mathematics 729 (1978), 93-104. Toral automorphisms come in three flavors, depending on the behavior on the generalized eigenspace for eigenvalues of modulus one (if any), and the specification behavior is different for each flavor.