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For spatio-temporal chaos observed in numerical simulations of the complex Ginzburg–Landau equation (CGL) and in experiments on inclined-layer convection (ILC) we report numerical and experimental data on the statistics of defects and of defect loops. These loops consist of defect trajectories in space–time that are connected to each other through the pairwise annihilation or creation of the associated defects. While most such loops are small and contain only a few defects, the loop distribution functions decay only slowly with the quantities associated with the loop size, consistent with power-law behavior. For the CGL, two of the three power-law exponents are found to agree, within our computational precision, with those from previous investigations of a simple lattice model. In certain parameter regimes of the CGL and ILC, our results for the single-defect statistics show significant deviations from the previously reported findings that the defect dynamics are consistent with those of random walkers that are created with fixed probability and annihilated through random collisions. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report experiments on defect-tracking in the state of undulation chaos observed in thermal convection of an inclined fluid layer. We characterize the ensemble of defect trajectories according to their velocities, relative positions, diffusion, and gain and loss rates. In particular, the defects exhibit incidents of rapid transverse motion which result in power law distributions for a number of quantitative measures. We examine connections between this behavior and Lévy flights and anomalous diffusion. In addition, we describe time-reversal and system size invariance for defect creation and annihilation rates. [ABSTRACT FROM AUTHOR]

The article introduces a series of articles which presents the winning entries in the Gallery of Nonlinear Images competition organized by the American Physical Society in its March 2009 meeting in Pittsburgh, Pennsylvania and was sponsored by the APS Topical Group on Statistical and Nonlinear Physics.

The article offers information on a physics research carried out by James G. Puckett and Karen E. Daniels of the North Carolina State University, Raleigh, North Carolina. Under it, they generated ensembles of two-dimensional granular configurations. It was seen that dense granular materials like glasses, exhibit slowing dynamics as they approach the jamming transition from a liquid like state.

The article examines the effects of varying substrate mobility from a liquid to solid. According to the author, the Marangoni effect in a surfactant could modified the contact line dynamics since it has the ability to create a surface tension gradient that generates pattern-forming instabilities. The instability of the surfactant-laden drop influenced by both the substrate fluidity and the surfactant condition was explored. Results of the research was further discussed by the author.

Studies the process through which a meteor comes to rest and forms a crater. Visualization of the forces generated in the impact bed through the use of photoelastic particles; Usability of the bidisperse mixture in suppressing crystallization; Snapshots of force chains during a meteor collision.