Abstract
Let Q(Δ) be the set of all integrable holomorphic quadratic differentials on the unit disk Δ. The subset Q0(Δ) of Q(Δ) is the set associated with T0 classes in the universal Teichmüller space T(Δ). In this paper, it is shown that Q0(Δ) is dense in Q(Δ). The infinitesimal version is also obtained.