We provide a new geometric
computation for the Jacobian of the Riemann surface of genus 4 associated to the
small stellated dodecahedron. Starting with Threlfall’s description, we introduce
other flat conformal geometries on this surface which are related to holomorphic
1-forms. They allow us to show that the Jacobian is isogenous to a fourfold
product of a single elliptic curve whose lattice constant can be determined
in two essentially different ways, yielding an unexpected relation between
hypergeometric integrals. We also obtain a new platonic tessellation of the
surface.
Keywords
Jacobians, flat structures, small stellated dodecahedron