  In the context of the non-relativistic theories, a generalization of the
Chern--Weil-theorem allows us to show that extended Chern--Simons actions for
gravity in d=4 invariant under some specific non-relativistic groups lead to
modified Poisson equations. In some particular cases, these modified equations
have the form of the so-called MOND approach to gravity. The modifications
could be understood as due to the effects of dark matter. This result could
leads us to think that dark matter can be interpreted as a non-relativistic
limit of dark energy.
