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arXiv · 1810.02838

Computation of extended symmetry groups for multidimensional subshifts with hierarchical structure

Abstract

Automorphism groups are intrincate conjugacy invariants for subshifts, which can reveal important features of the dynamical structure of a shift action. One important case is the study of automorphism groups when the underlying subshift has a very rigid structure, e.g. substitutive subshifts or aperiodic constructions with large-scale self-similarity, such as the Robinson shift. In this work we study the automorphism group of bijective substitutive subshifts, and a potential generalization in the form of the group of extended symmetries, studied previously by Michael Baake, John Roberts and Reem Yassawi (arXiv:1611.05756); these symmetries, by allowing for shearing and other deformations of the underlying group, may reveal additional information of a geometric nature about the structure of these subshifts.

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Álvaro Bustos. 2018-10-05. Computation of extended symmetry groups for multidimensional subshifts with hierarchical structure. https://arxiv.org/abs/1810.02838

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