We consider a brane world scenario in which the bulk action is assumed to
have the form of a generic function of the Ricci scalar f(R) and
derive the resulting Einstein field equations on the brane. In a constant
curvature bulk a conserved geometric quantity appears in the field equations
which can be associated with matter. We present cosmological and spherically
symmetric solutions by assuming specific forms for f(R) and show
that the former can explain an accelerated expanding universe while the latter
may account for galaxy rotation curves.Comment: 8 pages, 2 figures, to appear in EP