Combinatorics on words, facrordynamics and normal forms

Methods of symbolic dynamics play an essential role in the study of combinatorial properties of words, problems in number theory and the theory of dynamical systems. The paper is devoted
to the problems of combinatorics on words, its applications in algebra and dynamical systems.
Section 2.1 considers the one-dimensional case using the key example of Sturm’s words. The proof of the criterion for substitutionality of Sturm palindromes using the Rauzy induction is given, the case of one-dimensional facordynamics is considered. Section 2.2 discusses the shift of the torus and the Rauzy fractal that generates the word Tribonacci. The relationship between the periodicity of Rauzy’s schemes and the substitutionality of the word generated by this system is discussed. The implementation of the word Tribonacci through the rearrangement of line segments is given. An approach to the Pisot hypothesis is outlined. Section 2.3 talks about
unipotent torus transformations and billiards in polygons.
Chapter 3 talks about normal forms and the growth of groups and algebras. Chapter 4 is devoted to Rosie graphs, Gr¨obner bases and co-growth, and algebraic applications. Section 4.1
discusses the results in the combinatorics of multilinear words developed by V. N. Latyshev and the problems he posed. Section 4.2 talks about finitely defined objects and the problems of
controlling the relationships that define them. Section 4.3 describes some monomial algebras in terms of uniformly recurrent words.
Chapter 5 deals with the problem of height and normal forms.

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