Rate of Convergence to Separable Solutions of the Fast Diffusion   Equation
  We study the asymptotic behaviour near extinction of positive solutions of the Cauchy problem for the fast diffusion equation with a subcritical exponent. We show that separable solutions are stable in some suitable sense by finding a class of functions which belong to their domain of attraction. For solutions in this class we establish optimal rates of convergence to separable solutions. 
Marek Fila and Michael Winkler
math.AP