systems for some autonomous semilinear parabolic problems. We consider a prototype
problem, where the diffusion a_0(⋅) of a reaction-diffusion equation in a bounded domain Ω
is perturbed to a_ε(⋅). We show that the equilibria and the local unstable manifolds of the
perturbed problem are at a distance given by the order of ‖a_ε-a_0‖_∞. Moreover, the
perturbed nonlinear semigroups are at a distance ‖a_ε-a_0‖_∞^θ with θ<1 but arbitrarily …