  This paper describes the generation of initial conditions for numerical simulations in cosmology with multiple levels of resolution, or multiscale simulations. We present the theory of adaptive mesh refinement of Gaussian random fields followed by the implementation and testing of a computer code package performing this refinement called GRAFIC2. This package is available to the computational cosmology community at http://arcturus.mit.edu/grafic/ or by email from the author. 
Multiscale Gaussian Random Fields for Cosmological Simulations