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 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. [S0031-9007(98)07577-2].