Parole chiave

• hyperkähler manifold
• symplectic variety
• Enriques manifold
• nonysmplectic automorphisms

Abstract Automorphisms of hyperkähler manifolds have been studied for many different reasons: construct symplectic quotients or study fixed loci in order to find examples of irreducible symplectic varieties, define maps among different deformation families of HK manifolds, find new examples of Enriques manifolds, that are higher dimensional analogue of Enriques surfaces, and for which Pacienza and Sarti recently proved the Morrison-Kawamata cone conjecture. In the first part of the talk I will show a recent result about symplectic rigidity of hyperkähler manifolds of OG10 type. Then I will show how to construct examples of Enriques manifolds considering nonysmplectic automorphisms of a Laza-Saccà-Voisin manifold that are induced by a nonysmplectic automorphism of the underlying cubic fourfold.

The talk is based on a joint work with L. Giovenzana, Onorati and Veniani and on a joint work in progress with Billi, F. and L. Giovenzana.