Finite orbits in random subshifts of finite type

Abstract

For each $n, d \in \mathbb{N}$ and $0 < α< 1$, we define a random subset of $\mathcal{A}^{\{1, 2, \dots, n\}^d}$ by independently including each element with probability $α$ and excluding it with probability $1-α$, and consider the associated random subshift of finite type. Extending results of McGoff and of McGoff and Pavlov, we prove there exists $α_0 = α(d, |\mathcal{A}|) > 0$ such that for $α< α_0$ and with probability tending to $1$ as $n \to \infty$, this random subshift will contain only finitely many elements. In the case $d = 1$, we obtain the best possible such $α_0$, $1/|\mathcal{A}|$.