Berkovich approach to degenerations of hyper-Kähler varieties
To a degeneration of varieties, we can associate the dual intersection complex, a topological space that encodes the combinatoric of the central fiber and reflects the geometry of the generic fiber. The points of the dual complex can be identified to valuations on the function field of the variety, hence the dual complex can be embedded in the Berkovich space of the variety, defining a so-called Berkovich skeleton. Thanks to this interpretation, dual complexes can be studied both from the point of view of the birational geometry of the degeneration, and using Berkovich techniques. In this short talk I will explain how the second approach applies to the study of some degenerations of hyper-Kähler varieties. The results are in accordance with the predictions of mirror symmetry, and the recent work about the rational homology of dual complexes of degenerations of hyper-Kähler varieties, due to Kollár, Laza, Saccà and Voisin. This is joint work with Morgan Brown.