Local Rules for Computable Planar Tilings
  Aperiodic tilings are non-periodic tilings characterized by local constraints. They play a key role in the proof of the undecidability of the domino problem (1964) and naturally model quasicrystals (discovered in 1982). A central question is to characterize, among a class of non-periodic tilings, the aperiodic ones. In this paper, we answer this question for the well-studied class of non-periodic tilings obtained by digitizing irrational vector spaces. Namely, we prove that such tilings are aperiodic if and only if the digitized vector spaces are computable. 
Thomas Fernique (CNRS and Univ. Paris 13, France), Mathieu Sablik   (LATP - Univ. Aix-Marseille, France)
cs.FL cs.CC cs.DM math.CO