Back to the home pageThere's a Java applet here:
What you're looking at is the "phase space" of the particles-- the horizontal position of each particle is its physical location in one dimension, and the vertical position is its velocity. Thus, particles in the upper part of the picture can be observed to be moving to the right, while those in the lower part will be moving to the left. This particular simulation is initiated with two populations of charged particles: those moving to the right, which appear in the upper fuzzy line, and those moving left, in the lower fuzzy line. All the particles have the same mass and electric charge; you can think of them as being electrons, for example. This situation is well-known to be unstable to the so-called two-stream instability. The evolution of the instability is what you will see in this simulation. The surprising effect seen in the simulation is the formation of large vorticies in phase space, an effect which generally would be very hard to predict on the basis of a mathematical theory alone. This demonstrates the usefulness of particle simulation in studying the properties of multibody systems such as plasmas.
Bug: The applet stops with a floating point exception on some Windows 95 Netscape browsers.
Back to the Research Interests page