Due to the universality of gravity the “bare" scattering angle $\vartheta_0$ is unobservable, but it is possible to compare (\[teta\]) to the analogous result from DSR, obtained in the next section.

Comparison with DSR
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Now we are in a position to compare the two sets of variables constructed in the foregoing section with the “physical" and the “pseudo"-variables in DSR. Once the deformed, nonlinear relations for the physical variables are derived and modified kinematic relations are established with the aid of the linear pseudo-variables, they can in principle be forgotten, and all the consequences, the deformed dispersion relations between energy and momentum, the ensuing violations of conservation laws, etc. are ascribed to gravity.

Here we go the opposite way by asking the question whether a gravity-motivated deformation of SR is in its first approximation compatible with DSR. In the foregoing section we have seen that gravity influences particle scattering in the same way as if the particles had a slightly higher effective kinetic energy. In the following considerations this enhanced effective energy-momentum is set into relation with the DSR pseudo-variables and the actual asymptotic kinetic energy is related to the physical variables, as usual [@ww]. Also in view of 