Stochastic differential equations in a scale of Hilbert spaces. Global solutions

Abstract

A stochastic differential equation with coefficients defined in a scale of Hilbert spaces is considered. The existence, uniqueness and path-continuity of infinite-time solutions are proved by an extension of the Ovsyannikov method. These results are applied to a system of equations describing non-equilibrium stochastic dynamics of (real-valued) spins of an infinite particle system on a typical realization of a Poisson or Gibbs point process in ${\mathbb{R}}^n$. The paper improves the results of the work by the second named author “Stochastic differential equations in a scale of Hilbert spaces”, Electron. J. Probab. 23, where finite-time solutions were constructed.