Picture of the Day

Force Network

Granular materials, such as sand, behave in a surprising way: they can flow like a liquid, yet carry weight like a solid. We employ photographic techniques to study this behavior in a two dimensional model system: we use transparent disks made of photo-elastic material that changes its optical properties when subjected to a force. Images such as shown reveal the otherwise hidden and intricate force network between the particles, and continue to give surprising new insights in the interesting behavior of something as common as sand.

Visit Website | Image credit: Jie Ren, Joshua Dijksman, Robert P. Behringer; Duke University, Center for Nonlinear and Complex Systems