The nonlinear development of double tearing modes (DTMs) mediated by parallel electron viscosity in a large aspect ratio torus is simulated. The emphasis is placed on the mechanisms for the fast growth and sheared flow generation in the development of the DTMs. Four nonlinear developing stages: the early growth, transition, fast growth and decay, are found. In comparison with the helical magnet...

Models of three-dimensional space filling based on growth of two-dimensional sheets are proposed. Beginning from planar Eden-style growth of sheets, additional growth modes are introduced. These enable the sheets to form layered or disordered structures. The growth modes can also be combined. An off-lattice kinetic Monte Carlo-based computer algorithm is presented and used to study the kinetics...

We study radiation-hydrodynamical normal modes of radiation-supported accretion disks in the WKB limit. It has long been known that in the large optical depth limit the standard equilibrium is unstable to convection. We study how the growth rate depends on location within the disk, optical depth, disk rotation, and the way in which the local dissipation rate depends on density and pressure. The...