On hereditary properties of quantum group amenability

Abstract: Given a locally compact quantum group $\mathbb{G}$ and a closed quantum subgroup $\mathbb{H}$, we show that $\mathbb{G}$ is amenable if and only if $\mathbb{H}$ is amenable and $\mathbb{G}$ acts amenably on the quantum homogenous space $\mathbb{G}/\mathbb{H}$. We also study the existence of $L^1(\widehat{\mathbb{G}})$-module projections from $L^{\infty}(\widehat{\mathbb{G}})$ onto $L^{\infty}(\widehat{\mathbb{H}})$.