 The central role of inertial frames in Newtonian and Minkowski space-time theories, in sum, rested on their shared assumption of the uniformity of space-time. In Newtonian mechanics and special relativity, the formal relations between inertial coordinate systems—the Galilean and Lorentz transformations, respectively—correspond to symmetry transformations of uniform space-time, that is, a space-time with non-trivial global symmetries. In Einstein’s context, a coordinate transformation from the coordinates of one “stationary system” to those of another would generally not reflect a global symmetry of space-time, just to the extent that the two were relatively accelerating. 