%0 Journal Article %T Hypercontractivity of heat semigroups on free quantum groups %A Uwe Franz %A Guixiang Hong %A Fran£żois Lemeux %A Micha£żl Ulrich %J Mathematics %D 2015 %I arXiv %X In this paper we study two semigroups of completely positive unital self-adjoint maps on the von Neumann algebras of the free orthogonal quantum group $O_N^+$ and the free permutation quantum group $S_N^+$. We show that these semigroups satisfy ultracontractivity and hypercontractivity estimates. We also give results regarding spectral gap and logarithmic Sobolev inequalities. %U http://arxiv.org/abs/1511.02753v1