Title: Taming spatiotemporal chaos: periodic modulations of the control parameter.
Speaker: Professor M. Dennin
Speaker Info: UC Irvine
We will report on the taming of spatiotemporal chaos in an experimental system: electroconvection in the nematic liquid crystal I52. The spatiotemporal chaos is tamed through a periodic modulation of the control parameter. Electroconvection occurs when an ac voltage is applied across a liquid crystal sample. In the case of I52, there is a direct transition from a uniform state to a state that exhibits spatiotemporal chaos. Here spatiotemporal chaos refers to irregular behavior in space and time, even though the system is purely deterministic. The state of spatiotemporal chaos consists of the superposition of four linearly unstable modes that correspond to traveling waves. By modulating the control parameter at multiples of the traveling frequency, one can ?tame? the spatiotemporal chaos. This method also serves as a useful probe of the nature of the irregular dynamics. We will discuss both the effects of changing the modulation frequency on the degree of control and the insights gained into the dynamics by this probe of the system.Date: Friday, November 12, 1999