Guest Editor's Introduction: Frontiers of Simulation, Part II

In this second of two issues devoted to the frontiers of simulation, we feature four articles that illustrate the diversity of computational applications of complex physical phenomena. A major challenge for computational simulations is how to accurately calculate the effects of interacting phenomena, especially when such phenomena evolve with different time and distance scales and have very different properties. When time scales for coupling different effects are long compared with those that determine each effect's evolution separately then the system is "loosely coupled." It is then possible to couple several existing calculations together through an interface and obtain accurate answers.