Remarks on DSR and Gravity

Modifications of Special Relativity by the introduction of an invariant energy and/or momentum level (so-called Doubly Special Relativity theories, DSR) or by an energy-momentum dependence of the Planck constant (Generalized Uncertainty Principle, GUP) are compared with classical gravitational effects in an interaction processes. For the low energy limit of the usual formulations of DSR to be equivalent with Newtonian gravity, a restrictive condition is found. GUP yields an effective repulsion, in analogy to the gravitational repulsion in loop quantum cosmology.