2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/67540It is shown that a dynamical quantum group arising from a vertex-IRF transformation has a second realization with untwisted dynamical multiplication but nontrivial bigrading. Applied to the $\hbox{SL}(2;\mathbb{C})$ dynamical quantum group, the second realization is naturally described in terms of Koornwinder's twisted primitive elements. This leads to an intrinsic explanation why harmonic analysis on the ``classical'' $\hbox{SL}(2;\mathbb{C})$ quantum group with respect to twisted primitive elements, as initiated by Koornwinder, is the same as harmonic analysis on the $\hbox{SL}(2;\mathbb{C})$ dynamical quantum group.24 pagesQuantum AlgebraMathematical Physicstext