Computational Physics Across the Disciplines

In this informal talk, I will present two case studies of the unexpected convergence of computational techniques across disciplines. First, the marriage of neutron star astrophysics and the materials theory of the mechanical and thermal response of crystalline solids. Although the lower reaches of a neutron star host exotic nuclear physics, the upper few meters of the crust exist in a regime that is surprisingly amenable to standard molecular dynamics simulation, albeit in a physical regime of density order of magnitude of orders of magnitude different from those familiar to most condensed matter folk. Computational results on shear strength, thermal conductivity, and other properties here are very relevant to possible gravitational wave signals from these sources. The second example connects not two disciplines of computational physics, but experimental and computational physics, and {\it not} from the traditional direction of computational progressively approaching experiment. Instead, experiment is approaching computation: regular lattices of single-domain magnetic islands whose magnetic microstates can be exhaustively enumerated by magnetic force microscopy. There resulting images of island magnetization patterns look essentially like the results of Monte Carlo simulations of Ising systems... statistical physics with the microstate revealed.