2012/05/28 by Goswami, Debashish
#20G42 #58B34 #81R50 #81R60 #FOS: Mathematics #Metric Geometry (math.MG) #Operator Algebras (math.OA) #Quantum Algebra (math.QA)
paper · doi:10.48550/arxiv.1205.6099
We formulate a definition of isometric action of a compact quantum group (CQG) on a compact metric space, generalizing Banica's definition for finite metric spaces. For metric spaces (X,d) which can be isometrically embedded in some Euclidean space, we prove the existence of a universal object in the category of the compact quantum groups acting isometrically on (X,d). In fact, our existence theorem applies to a larger class, namely for any compact metric space (X,d) which admits a one-to-one continuous map f : X \raro \IRn for some n such that d0(f(x),f(y))=ϕ(d(x,y)) (where d0 is the Euclidean metric) for some homeomorphism ϕ of \IR+. As concrete examples, we obtain Wang's quantum permutation group \clsn+ and also the free wreath product of \IZ2 by \clsn+ as the quantum isometry groups for certain compact connected metric spaces constructed by taking topological joins of intervals in \citehuang1.