Subshifts of finite type and matching for intermediate $\beta$-transformations

Abstract

We focus on the relationships between matching and subshift of finite type for intermediate $\beta$-transformations $T_{\beta,\alpha}(x)=\beta x+\alpha $ ($\bmod$ 1), where $x\in[0,1]$ and $(\beta,\alpha) \in \Delta:= \{ (\beta, \alpha) \in \mathbb{R}^{2}:\beta \in (1, 2) \; \rm{and} \; 0 < \alpha <2 - \beta\}$. We prove that if the kneading space $\Omega_{\beta,\alpha}$ is a subshift of finite type, then $T_{\beta,\alpha}$ has matching. Moreover, each $(\beta,\alpha)\in\Delta$ with $T_{\beta,\alpha}$ has matching corresponds to a matching interval, and there are at most countable different matching intervals on the fiber. Using combinatorial approach, we construct a pair of linearizable periodic kneading invariants and show that, for any $\epsilon>0$ and $(\beta,\alpha)\in\Delta$ with $T_{\beta,\alpha}$ has matching, there exists $(\beta,\alpha^{\prime})$ on the fiber with $|\alpha-\alpha^{\prime}|<\epsilon$, such that $\Omega_{\beta,\alpha^{\prime}}$ is a subshift of finite type. As a result, the set of $(\beta,\alpha)$ for which $\Omega_{\beta,\alpha}$ is a subshift of finite type is dense on the fiber if and only if the set of $(\beta,\alpha)$ for which $T_{\beta,\alpha}$ has matching is dense on the fiber.