do with the concept of dimension which, for all RIFs, is the same i.e. the time $T$ (the second, in units, where $c=1$, see e.g. [@mikebook]). Dicke is aware of that and then says [*“ Generally there may be more than one feasible way of establishing the equality of units at different spacetime points”*]{} [@Dicke62]. It is essential to stress that such an approach is based on conventions which may lead to absurd results in real measurements. Geometrically it is a 1:1 map of two points defining a spacelike interval from the rest space of one observer at a spacetime point to a spacelike plane of another observer at another spacetime point. This definition it is not a coordinate transformation and there is no point or meaning to consider symmetry invariance with this transformation. Dicke says [*“It is evident that the equations of motion of matter must be invariant under a general coordinate dependent transformation of units”*]{} [@Dicke62]. This is a misunderstanding that can give rise to confusion. The method of comparing lengths at different spacetime points is a kinematic assumption while equations of motion give dynamics.

Furthermore, Dicke’s argument is purely classical. In cosmology, black hole physics, and quantum 