Date(s) : 04/02/2020
11 h 00 min - 12 h 00 min
Andrei ROMASHCHENKO (LIRMM, CNRS, Montpellier)
In symbolic dynamics, the following three classes of subshifts play an important role: subshifts of finite type, sofic shifts, and effective
shifts, which are nested inside each other. The boundaries between these classes are pretty well understood in dimension 1, but the multidimensional subshifts are more elusive.
In this talk, we focus on the borderline between sofic and effective but not sofic subshifts, and discuss techniques suitable to prove that
some specific explicitly given subshift is not sofic. We argue that Kolmogorov complexity is a helpful tool in these proofs.