Weierstrass meets Enriques

Understand

We study in detail the degeneration of K3 to T^4/Z_2.

• We obtain an explicit embedding of the lattice of collapsed cycles of T^4/Z_2 into the lattice of integral cycles of K3 in two different ways.
• Our first method exploits the duality to the heterotic string on T^3.
• This allows us to describe the degeneration in terms of Wilson lines.