We study the Langevin dynamics of the standard random heteropolymer model b
y mapping the problem to a supersymmetric field theory using the Martin-Sig
gia-Rose formalism. The resulting model is solved nonperturbatively employi
ng a Gaussian variational approach. In constructing the solution, we assume
that the chain is very long and impose the translational invariance which
is expected to be present in the bulk of the globule by averaging over the
center of mass coordinate. In this way we derive equations of motion for th
e correlation and response functions C(t.t') and R(t,t'). The order paramet
ers are extracted from the asymptotic behavior of these functions. We find
a dynamical phase diagram with frozen (glassy) and melted (ergodic) phases.
In the glassy phase the system fails to reach equilibrium and exhibits agi
ng of the type found in p-spin glasses. Within the approximations used in t
his study, the random heteropolymer model can be mapped to the problem of a
manifold in a random potential with power law correlations.