A geometric flow based in the Riemann-Christoffel curvature tensor that in
two dimensions has some common features with the usual Ricci flow is presented.
For n dimensional spaces this new flow takes into account all the components
of the intrinsic curvature. For four dimensional Lorentzian manifolds it is
found that the solutions of the Einstein equations associated to a "detonant"
sphere of matter, as well, as a Friedman-Roberson-Walker cosmological model are
examples of Riemann-Christoffel flows. Possible generalizations are mentioned.Comment: 3 pages, RevTex,small changes, Int. J. Theor. Phys. (in press
