On a characterization of bilinear forms on the Dirichlet space

Arcozzi, Rochberg, Sawyer and Wick obtained a characterization of the holomorphic functions $b$ such that the Hankel type bilinear form $T_{b}(f,g)= \int _{\D }(I+R)(fg)(z) \overline {(I+R)b(z)}dv(z)$ is bounded on ${\mathcal D}\times {\mathcal D}$, where ${\mathcal D}$ is the Dirichlet space. In this paper we give an alternative proof of this characterization which tries to understand the similarity with the results of Maz$'$ya and Verbitsky relative to the Schrödinger forms on the Sobolev spaces $L_2^1(\mathbb{R}^n)$.