1 Hilbert modular surfaces 3 1.1 The Hilbert modular group . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2 The Baily-Borel compactification . . . . . . . . . . . . . . . . . . . . . . . 6 1.2.1 Siegel domains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.3 Hilbert modular forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.4 Mk(Γ) is finite dimensional...

Classically, there are many interesting connections between differential operators and the theory of elliptic modular forms and many interesting results have been explored. In particular, it has been known for some time how to obtain an elliptic modular form from the derivatives ofN elliptic modular forms, which has already been studied in detail by R. Rankin in [9] and [10]. When N = 2, as a s...

We give a short and “soft” proof of the asymptotic orthogonality of Fourier coefficients of Poincaré series for classical modular forms as well as for Siegel cusp forms, in a qualitative form.

We determine an explicit formula for a Rankin-Cohen bracket for Siegel modular forms of degree n on a certain subgroup of the symplectic group. Moreover, we lift that bracket via a Poincaré series to a Siegel cusp form on the full symplectic group.