Abstract
We study the dynamics of a directed manifold of internal dimension
D in a d-dimensional quenched random force field. We obtain an
exact solution for d → ∞ and a Hartree approximation for
finite d. They yield a Flory-like roughness exponent ζ and a
nontrivial anomalous diffusion exponent ν continuously dependent
on the ratio gT/gL of divergence-free (gT) to
potential (gL) disorder strength. For the particle (D = 0)
our results agree with previous order 2 RG calculations.
The time-translational invariant dynamics for gT > 0 smoothly
crosses over to the previously studied ultrametric aging solution in
the potential case.