TY - JOUR AU - Kuznetsova, Yulia PY - 2015/06/26 Y2 - 2024/03/29 TI - A Duality of Locally Compact Groups That Does Not Involve the Haar Measure JF - MATHEMATICA SCANDINAVICA JA - Math. Scand. VL - 116 IS - 2 SE - Articles DO - 10.7146/math.scand.a-21162 UR - https://www.mscand.dk/article/view/21162 SP - 250-286 AB - We present a simple and intuitive framework for duality of locally compacts groups, which is not based on the Haar measure. This is a map, functorial on a non-degenerate subcategory, on the category of coinvolutive Hopf $C^*$-algebras, and a similar map on the category of coinvolutive Hopf-von Neumann algebras. In the $C^*$-version, this functor sends $C_0(G)$ to $C^*(G)$ and vice versa, for every locally compact group $G$. As opposed to preceding approaches, there is an explicit description of commutative and co-commutative algebras in the range of this map (without assumption of being isomorphic to their bidual): these algebras have the form $C_0(G)$ or $C^*(G)$ respectively, where $G$ is a locally compact group. The von Neumann version of the functor puts into duality, in the group case, the enveloping von Neumann algebras of the algebras above: $C_0(G)^{**}$ and $C^*(G)^{**}$. ER -