Generalisation of the tetragonal construction
Seminar Room 1, Newton Institute
The Donagi conjecture states that the Prym map is injective at a double cover of a curve if the curve does not admit a morphism of degree less or equal to 4 onto the projective line. The talk focusses on 2 subjects, I will explain why the existing proofs of the tetragonal construction do not generalize and then outline the proof of a generalization which give counterexamples to the conjecture. This is joint work with Elham Izadi.