Asymptotic pressure on Cayley graphs of finitely generated semigroups

The vertices of the Cayley graph of a finitely generated semigroup form a set of sites which can be labeled by elements of a finite alphabet in a manner governed by a nonnegative real interaction matrix, respecting nearest neighbor adjacency restrictions. To the set of these configurations one can associate a pressure, which is defined as the limit, when it exists, of averages of the logarithm of the partition function over certain finite subgraphs. We prove that for shifts of finite type on generalized Fibonacci trees, under an added condition, the limit exists and is given by an infinite series. We also show that the limit of any cluster points of the pressure on finite subtrees as the number of generators grows without bound, which we call the asymptotic pressure, equals the logarithm of the maximum row sum of the interaction matrix.Comment: Clarified a hypothesis of the first theorem and the proof of the secon

Topological Entropy for Shifts of Finite Type Over Z\mathbb{Z} and Tree

We study the topological entropy of hom tree-shifts and show that, although the topological entropy is not conjugacy invariant for tree-shifts in general, it remains invariant for hom tree higher block shifts. In doi:10.1016/j.tcs.2018.05.034 and doi:10.3934/dcds.2020186, Petersen and Salama demonstrated the existence of topological entropy for tree-shifts and $h(\mathcal{T}_X) \geq h(X)$, where $\mathcal{T}_X$ is the hom tree-shift derived from $X$. We characterize a necessary and sufficient condition when the equality holds for the case where $X$ is a shift of finite type. In addition, two novel phenomena have been revealed for tree-shifts. There is a gap in the set of topological entropy of hom tree-shifts of finite type, which makes such a set not dense. Last but not least, the topological entropy of a reducible hom tree-shift of finite type is equal to or larger than that of its maximal irreducible component

The strip entropy approximation of Markov shifts on trees

The strip entropy is studied in this article. We prove that the strip entropy approximation is valid for every ray of a golden-mean tree. This result extends the previous result of [Petersen-Salama, Discrete \& Continuous Dynamical Systems, 2020] on the conventional 2-tree. Lastly, we prove that the strip entropy approximation is valid for eventually periodic rays of a class of Markov-Cayley trees

On the topological pressure of axial product on trees

This article investigates the topological pressure of isotropic axial products of Markov subshift on the $d$-tree. We show that the quantity increases with dimension $d$, and demonstrate that, with the introduction of surface pressure, the two types of pressure admit the same asymptotic value. To this end, the pattern distribution vectors and the associated transition matrices are introduced herein to partially transplant the large deviation theory to tree-shifts, and so the increasing property is proved via an almost standard argument. An application of the main result to a wider class of shift spaces is also provided in this paper, and numerical experiments are included for the purpose of verification