37 citations · 53 across the 16 of their papers we have counts for
5 papers · 2 filters
Constructions with Countable Subshifts of Finite Type
Ville Salo, Ilkka Törmä
We present constructions of countable two-dimensional subshifts of finite type (SFTs) with interesting properties. Our main focus is on properties of the topological derivatives an…
Playing with Subshifts
Ville Salo, Ilkka Törmä
We study the class of word-building games, where two players pick letters from a finite alphabet to construct a finite or infinite word. The outcome is determined by whether the re…
A Uniquely Ergodic Cellular Automaton
Ilkka Törmä
We construct a one-dimensional uniquely ergodic cellular automaton which is not nilpotent. This automaton can perform asymptotically infinitely sparse computation, which neverthele…
Category Theory of Symbolic Dynamics
Ville Salo, Ilkka Törmä
We study the central objects of symbolic dynamics, that is, subshifts and block maps, from the perspective of basic category theory, and present several natural categories with sub…
Block Maps between Primitive Uniform and Pisot Substitutions
Ville Salo, Ilkka Törmä
In this article, we prove that for all pairs of primitive Pisot or uniform substitutions with the same dominating eigenvalue, there exists a finite set of block maps such that ever…