Nonlinear Rheology of Colloidal Suspensions

Recently, an extension of Mode Coupling Theory (MCT) to systems under steady shearing was developed that unites the fields of rheology and glass transition for supercooled liquids. Central to the first-principle approach are generalized Green-Kubo relations that contain the complete transient time evolution of the system. In detail, the theory predicts shear thinning, yielding of colloidal glasses, a speed up of structural relaxation under shear and a dependence of the microstructure on the shear rate as a result of shear advected density fluctuations. After a brief introduction to the framework I will present this time some first results of the full microscopic approach in plain Couette flow for a hard disc fluid, including density correlation functions, shear moduli, stresses and viscosity, and the distortion of the static structure in simple shear flow.