Analogies between evolutionary dynamics and statistical mechanics, such as Fisher’s second-law-like ”fundamental theorem of natural selection” and Wright’s “fitness landscapes”, have had a deep and fruitful influence on the development of evolutionary theory. Here I discuss a new conceptual link between evolution and statistical physics. I argue that natural selection can be viewed as a coarsen...

A proper coarse variable set for Algebraic Multigrid (AMG) solvers can be constructed using Compatible Relaxation (CR). For a given coarse set, CR is a modified relaxation scheme that keeps the values of the coarse variables intact. Its convergence factor is a predictor of the potential AMG efficiency, similarly to the smoothing factor in geometric multigrid. A practical CR-based coarse set con...

reservoir models with many grid blocks suffer from long run time; it is hence important to deliberatea method to remedy this drawback. usual upscaling methods are proved to fail to reproduce fine gridmodel behaviors in coarse grid models in well proximity. this is attributed to rapid pressure changesin the near-well region. standard permeability upscaling methods are limited to systems with lin...

Abstract. Previously we examined the black box multigrid approach to systems of equations. The approach was a direct extension of the methodology used for scalar equations; that is, interpolation and residual weighting were operator induced, and coarsening employed a Galerkin strategy. The application was to standard coarsening of the unknowns. In this paper we consider a semicoarsening approac...

The role of memory is crucial in determining the properties of many dynamical processes in statistical physics. We show that the simple addition of memory, in the form of noise reduction, modifies the overall scaling behavior of the voter model, introducing an effective surface tension analogous to that recently observed in memory-based models of social dynamics. The numerical results for low-d...