  The dynamics of phase separation for a binary fluid subjected to a uniform
shear are solved exactly for a model in which the order parameter is
generalized to an n-component vector and the large-n limit taken.
Characteristic length scales in directions parallel and perpendicular to the
flow increase as (t^5/\ln t)^{1/4} and (t/\ln t)^{1/4} respectively. The
structure factor in the shear-flow plane exhibits two parallel ridges as
observed in experiment.
