Pull-back attractors for three-dimensional Navier-Stokes-Voigt equations in some unbounded domains

We study the first initial-boundary-value problem for the three-dimensional non-autonomous Navier-Stokes-Voigt equations in an arbitrary (bounded or unbounded) domain satisfying the Poincare inequality. The existence of a weak solution to the problem is proved by using the Faedo-Galerkin method. We then show the existence of a unique minimal finite-dimensional pull-back D-sigma-attractor for the process associated with the problem, with respect to a large class of non-autonomous forcing terms. We also discuss relationships between the pull-back attractor, the uniform attractor and the global attractor.