Strong coupling expansion is computed for the Einstein equations in vacuum in
the Arnowitt-Deser-Misner (ADM) formalism. The series is given by the duality
principle in perturbation theory as presented in [M.Frasca, Phys. Rev. A 58,
3439 (1998)]. An example of application is also given for a two-dimensional
model of gravity expressed through the Liouville equation showing that the
expansion is not trivial and consistent with the exact solution, in agreement
with the general analysis. Application to the Einstein equations in vacuum in
the ADM formalism shows that the spacetime near singularities is driven by
space homogeneous equations.