Abstract:
In the work the authors propose to apply the notion of a local group in the theory of $C^*$-algebras. The regular representation is defined, which is a $*$-representation and generates the reduced $C^*$-algebra. A class of local groups is constructed, generated by the subset $P$ of a discrete group, for which the notion of the $P$-regular representation is defined, which is a strong $*$-representation and generates the corresponding reduced algebra. Examples of simple algebras are given, constructed from given subsets of an abelian group.