We study the Langevin algorithm on C(infinity) n-dimensional compact c
onnected Riemannian manifolds and on R(n), allowing the energy functio
n U to vary with time. We find conditions under which the distribution
of the process at hand becomes indistinguishable, as t --> infinity f
rom the ''instantaneous'' equilibrium distribution. Such conditions do
not necessarily imply that U (t) converges pointwise as t --> infinit
y.