“…3 contact with Connes' enterprise, resulted, following Wang's pioneering work on quantum symmetries of finite spaces [Wan98], in several constructions and insights. Let us mention, albeit incompletely, the work of: • Banica, Bichon, and collaborators on quantum symmetries of discrete structures (see [Ban05a,Ban05b,Bic03]); • Goswami, Bhowmick, and collaborators on quantum isometries of spectral triples (see [BG09, BG19, GJ18, Gos20]); • Banica, Skalski, and collaborators on quantum symmetries of C * -algebras equipped with orthogonal filtrations (see [BMRS19,BS13]); and • more recently, Goswami and collaborators on quantum symmetries of subfactors (see [BCG22]). The study of quantum symmetries of C * -algebras have also been rewarding enough.…”