Jie Ren's first place photoPhysics graduate student Jie Ren and post doc Joshua Dijksman took first and second prize, respectively, in the Mahato Memorial Scientific Visualization Contest sponsored by Duke's engineering department. The contest honors the memory of engineering graduate student Abhijit Mahato, who was murdered in January 2008. For more information and to see the winning photos, go here. Click these links to view full-sized and high resolution versions of Ren and Dijksman's winning photos. Follow the link to read more to view the captions describing the physics behind each image.Jie Ren's image caption: "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. "Josh Dijksman's Winning 2nd Place PhotoJoshua Dijksman's 2nd place photo is above. It is called ""Bubbles in a Petri Dish." His caption reads: "This is an image of a layer of UV-light exposed fluorescent foam bubbles in a petri dish, squeezed between a liquid and the confining lid. Such monolayers of bubbles are used as a model system to study the intricate and poorly understood mechanical behavior of disordered systems like sand, mayonnaise and, yes, shaving foam. This image is one of the first proof-of-principles that shows that a fluorescent dye in the fluid can greatly facilitate recognizing the foam bubbles, which in these studies is an essential yet otherwise strenuous task. "