The universality of the Laplace–Runge–Lenz symmetry in all rotationally symmetric systems is discussed. The independence of the symmetry on the type of interaction is proven using only the most generic properties of the Poisson brackets. Generalized Laplace–Runge–Lenz vectors are definable to be constant (not only piecewise conserved) for all cases, including systems with open orbits. Applications are included for relativistic Coulomb systems and electromagnetic/gravitational systems in the post-Newtonian approximation. The evidence for the relativistic origin of the symmetry are extended to all centrally symmetric systems.
U. Ben-Ya'acov, "Laplace–Runge–Lenz symmetry in general rotationally symmetric systems", J. Math. Phys. 51, 122902 (2010).