5 citations · 9 across the 11 of their papers we have counts for
14 papers
Two block gluing constructions
Ville Salo, Ilkka Törmä
We prove two existence results about block gluing in two-dimensional SFTs. First, a large class of functions between exponential and logarithmic can be realized as block gluing fun…
Multidimensional tilings and MSO logic
Rémi Pallen, Ilkka Törmä
We define sets of coulourings of the infinite discrete plane using monadic second order (MSO) formulas. We determine the complexity of deciding whether such a formula defines a sub…
Symbol Frequencies in Surjective Cellular Automata
Benjamin Hellouin de Menibus, Ilkka Törmä, Ville Salo
We study the behavior of probability measures under iteration of a surjective cellular automaton. We solve the following question in the negative: if the initial measure is ergodic…
On Countable SFT Covers of Sparse Multidimensional Shift Spaces
Ilkka Törmä
A multidimensional sofic shift is called countably covered if it has an SFT cover containing only countably many configurations. In contrast to the one-dimensional setting, not all…
Arithmetical Complexity of the Language of Generic Limit Sets of Cellular Automata
Solène J. Esnay, Alonso Núñez, Ilkka Törmä
The generic limit set of a dynamical system is the smallest set that attracts most of the space in a topological sense: it is the smallest closed set with a comeager basin of attra…
What can oracles teach us about the ultimate fate of life?
Ville Salo, Ilkka Törmä
We settle two long-standing open problems about Conway's Life, a two-dimensional cellular automaton. We solve the Generalized grandfather problem: for all , there exists…