On a class of poly-context-free groups generated by automata

A Fractal Non-Contracting Class of Automata Groups

A Class of Two Generated Automaton Groups on a Three Letter Alphabet

Groups with poly-context-free word problem

We consider the class of groups whose word problem is poly-contextfree; that is, an intersection of finitely many context-free languages. We show that any group which is virtually a finitely generated subgroup of a direct product of free groups has poly-context-free word problem, and conjecture that the converse also holds. We prove our conjecture for several classes of soluble groups, includin...

A Class of P Automata for Characterizing Context-free Languages

Membrane systems, or P systems, are distributed computing models inspired by the functioning of the living cell. Their main components are membrane structures consisting of membranes hierarchically embedded in the outermost skin membrane. Each membrane encloses a region containing a multiset of objects and possibly other membranes. Each region has an associated set of operators working on the o...

Groups and Semigroups Generated by Automata

In this dissertation we classify the metabelian groups arising from a restricted class of invertible synchronous automata over a binary alphabet. We give faithful, self-similar actions of Heisenberg groups and upper triangular matrix groups. We introduce a new class of semigroups given by a restricted class of asynchronous automata. We call these semigroups " expanding automaton semigroups ". W...