The positive spin ladder
representations of G = U(p,q), which occur naturally on a Fock space ℱp,q, can each
be realized within a space of polynomial-valued functions on the bounded realization
Dp,q of G∕K. This is achieved via an integral transform constructed by Mantini,
1985. An inversion formula is given for Mantini’s transform. Then, natural unitary
structures are obtained for the geometric realizations of the positive spin
ladder representations over G∕K by using the inversion formula to pull the
representations back to the Fock space setting, where the unitary structures are
well-known.