18 research outputs found
An automata group of intermediate growth and exponential activity
We give a new example of an automata group of intermediate growth. It is
generated by an automaton with 4 states on an alphabet with 8 letters. This
automata group has exponential activity and its limit space is not simply
connected
On Sushchansky p-groups
We study Sushchansky p-groups. We recall the original definition and
translate it into the language of automata groups. The original actions of
Sushchansky groups on p-ary tree are not level-transitive and we describe their
orbit trees. This allows us to simplify the definition and prove that these
groups admit faithful level-transitive actions on the same tree. Certain branch
structures in their self-similar closures are established. We provide the
connection with, so-called, G groups that shows that all Sushchansky groups
have intermediate growth and allows to obtain an upper bound on their period
growth functions.Comment: 14 pages, 3 figure
Groups of given intermediate word growth
We show that there exists a finitely generated group of growth ~f for all
functions f:\mathbb{R}\rightarrow\mathbb{R} satisfying f(2R) \leq f(R)^{2} \leq
f(\eta R) for all R large enough and \eta\approx2.4675 the positive root of
X^{3}-X^{2}-2X-4. This covers all functions that grow uniformly faster than
\exp(R^{\log2/\log\eta}).
We also give a family of self-similar branched groups of growth
~\exp(R^\alpha) for a dense set of \alpha\in(\log2/\log\eta,1).Comment: small typos corrected from v
On the Word and Period Growth of some Groups of Tree Automorphisms
We generalize a class of groups defined by Rostislav Grigorchuk to a much
larger class of groups, and provide upper and lower bounds for their word
growth (they are all of intermediate growth) and period growth (under a small
additional condition, they are periodic).Comment: to appear in Comm. Algebr
On the spectrum of asymptotic entropies of random walks
Abstract. Given a random walk on a free group, we study the random walks it
induces on the group's quotients. We show that the spectrum of asymptotic
entropies of the induced random walks has no isolated points, except perhaps
its maximum
On the spectrum of asymptotic entropies of random walks
Given a random walk on a free group, we study the random walks it induces on the group's quotients. We show that the spectrum of asymptotic entropies of the induced random walks has no isolated points, except perhaps its maximum