Some ball quotients with a Calabi–Yau model

Abstract:

Recently we determined explicitly a Picard modular variety of general type. On the regular locus of this variety there are holomorphic three forms which have been constructed as Borcherds products. Resolutions of quotients of this variety, such that the zero divisors are in the branch locus, are candidates for Calabi–Yau manifolds. Here we treat one distinguished example for this. In fact we shall recover a known variety given by the equations \[ X_0X_1X_2=X_3X_4X_5, X_0^3+X_1^3+X_2^3=X_3^3+X_4^3+X_5^3. \] as a Picard modular variety. This variety has a projective small resolution which is a rigid Calabi–Yau manifold ($h^{12}=0$) with Euler number $72$.