Cubic fourfolds, hyper-Kähler manifolds and their degenerations

Apparaît dans la collection : Complex Analytic and Differential Geometry

There at least three families of hyper-K ̈ahler manifolds built from cubic fourfolds, the most recently discovered one being the compactified intermediate Jacobian fibrations I constructed with Laza and Sacca. In a joint work with Koll ́ar, Laza and Sacca, we provide an easy way to compute their deformation types, by proving that if the central fiber of a degeneration of hyper-Kähler manifolds has one component which is not uniruled, then after base-change the family becomes fiberwise birational to a family of smooth hyper-Kähler manifolds.