Continuity of Lyapunov exponents for polynomial automorphisms of ${\mathbb{C}}^2$

Abstract

We prove two continuity theorems for the Lyapunov exponents of the maximal entropy measure of polynomial automorphisms of ${\mathbb{C}}^2$. The first continuity result holds for any family of polynomial automorphisms of constant dynamical degree. The second result is the continuity of the upper exponent for families degenerating to a 1-dimensional map.