Dynamical Dimension of Defects in Spatiotemporal Chaos

We utilize the dynamical fluctuations in spatiotemporal chaotic systems to elucidate the dynamical role of topological defects. We find that each defect in a representative defect-mediated system is associated with one to two degrees of dynamical freedom. Furthermore, we find that a significant fraction of the total degrees of freedom is {ital not} associated with the defects, and, in fact, appear to be related to the background phase turbulence. This new understanding of defect-mediated chaos provides hope that these complicated systems may be amenable to reduced statistical descriptions. {copyright} {ital 1998} {ital The American Physical Society }