  We study thermally activated dynamics using functional renormalization within
the field theory of randomly pinned elastic systems, a prototype for glasses.
It appears through an essentially non-perturbative boundary layer in the
running effective action, for which we find a consistent scaling ansatz to all
orders. We find that in the statics the boundary layer describes the physics of
rare low energy metastable states as suggested by a phenomenological droplet
picture. The extension to equilibrium dynamics mandates a non-trivial broad
distribution of relaxation times for the large scale modes, hitherto neglected
in analytic calculations.
