Specular sets
Valérie Berthé, Clelia De Felice, Vincent Delecroix, Francesco Dolce, Julien Leroy, Dominique Perrin, Christophe Reutenauer, Giuseppina Rindone · arXiv (Cornell University) · 2015
We introduce the notion of specular sets which are subsets of groups called here specular and which form a natural generalization of free groups. These sets are an abstract generalization of the natural codings of linear involutions. We prove several results concerning the subgroups generated by return words and by maximal bifix codes in these sets.