Long wavelength instability for uniform shear flow.

Uniform shear flow is a prototype non-equilibrium state admitting detailed study at both the macroscopic and microscopic levels via theory and computer simulation. It is shown that the hydrodynamic equations for this state have a long wavelength instability. This result is obtained first from the NavierStokes equations and shown to apply at both low and high densities. Next, higher order rheological effects are included using a model kinetic theory. The results are compared favorably to those from Monte Carlo simulation. PACS numbers: 47.20.Ft, 05.20.Dd, 05.60.+w, 0.5.70Ln Typeset using REVTEX