About the Images . . .Related Page:
Cross-Linked Polymer ChainsMolecular dynamics computer simulation showing the cross-linking of polymer molecules. The colors represent separate clusters which, in the real-time simulation, are constantly reconfiguring themselves as cross links are added to or removed from the system. The presence of cross-links is governed by the temperature of the system. Students discover that at a critical temperature the entire system undergoes a gelation transition characterized by polymer chains spanning the entire system. Image courtesy of Sergey Buldyrev.
The AnthillThis model is a natural two-dimensional extension of a random walk. Displayed is the territory covered by 500 random walkers. As the number of walkers increases the resulting interface becomes more smooth. This model describes reaction-diffusion systems as well as population dynamics (species dispersal). See Nature 30 January 1992. This article was picked up by Science News and Discover magazines. Image courtesy of Paul Trunfio.
Hele-ShawThis image, created as part of the Dance of Chance exhibit, was created by filling a 1/80 inch space between to plastic plates with glycerol and then injecting air into the space. Food coloring is used to elucidate the ``fingering'' pattern produced. Image courtesy of Eshel Ben-Jacob.
Diffusion-Limited AggregationThe Diffusion-limited aggregation model grows as a consequence of sticking two-dimensional random walkers. The walker moves randomly until it "touches" the growing seed. Student controls the screen size, stepping rate, attraction of the seed for the walker, as well as a number of other parameters---thereby allowing the student to discover structures which are aesthetically beautiful, unique, and at the same time have physical meaning. Such structures arise naturally in fields of science ranging from electrochemical deposition to various "breakdown phenomena" such as dielectric breakdown, viscous fingering, chemical dissolution, and the rapid crystallization of lava. This was the subject of research by high school student Dan Stevenson who was a finalist in the 1993 Westinghouse Science Competition. Image courtesy of Paul Trunfio.
Liquid WaterA single frame in a graduate student-generated ``movie'' of the bond network in liquid water, showing a computer simulation of 216 water molecules situated inside a box 18.6 Angstroms on an edge. See Science News 4/14/90. Image courtesy of Mark Gyure.
Fractal SurfacesSurface growth in a disordered three-dimensional medium. Computer simulations were generated using the directed percolation depinning model of interface growth which is characterized by a depinning threshold that occurs only in the presence of a directed surface of pinning sites. Image courtesy of Paul Trunfio.
LichtenbergThis image, created as part of the Dance of Chance Exhibit, was generated with a process known as dielectric breakdown by charging a piece of clear acrylic plastic with electrons and then discharging it. Image courtesy of Ken Brecher and Peter Garik
ECDThis image, created as part of the Dance of Chance Exhibit, depicts the growth of a metal crystalline deposit. A negatively charged wire was sandwiched between two metal plates with a solution of zinc sulfate. The positively charged zinc ions are attracted to the wire, and the resulting pattern forms. Image courtesy of Mitsugu Matsushita.
ErosionThis photograph, as part of the Dance of Chance Exhibit, was taken in Alaska and depicts a patterning in the Earch called an ``alluvial fan.'' Image courtesy of Duncan Fitzgerald.
TermitesThis image, created as part of the Dance of Chance exhibit, shows the branching pattern produced by approximatly 150 termites in a region of sand between two plates seperated by 1/32 inch. The termites create this pattern as they forage through the sand in search of food. Image courtesy of Peter Garik.
BacteriaThis image, created as part of the Dance of Chance exhibit, depicts the fingering pattern produced by bacteria growth under insufficient nutrient conditions. Image courtesy of Peter Garik.
|