  Employing the concept of the microsymmetry group (definition 4.1),  Coleman and Korté (1982) have analyzed Weyl’s plasticine  example in the following way: Consider a space-time manifold equipped only with a differentiable structure, the plasticine of Weyl’s  example. Then our spacetime does not have an affine, conformal,  projective or metric structure defined on it. In such a world it is  possible do define curves and paths; however, there are no preferred  curves or paths. Since there is only the differentiable structure,  one may apply any diffeomorphism; that is, all  diffeomorphisms preserve this structure; consequently, in the  absence of a post-differential-topological structure, the  microsymmetry group at any event \(p\) is an infinite-parameter  group isomorphic to the group of all invertible formal power series  in four variables. If there is no post-differentiable topological  geometric field in the neighbourhood of a point, then all of these  infinite parameters may be chosen freely within rather broad limits.  Clearly then, given an infinite number of parameters, one can, as  Weyl says, straighten out an arbitrary pattern of world lines  (fibers) in the neighbourhood of any event. Now suppose that there  exists a post-differentiable topological geometric field, namely, the projective structure at any event of spacetime. Then the  microsymmetry group that preserves that structure is a 20-parameter  Lie group (see Coleman and Korté (1981)). Thus instead of an  infinity of degrees of freedom, only twenty degrees of freedom may be used to actively deform the neighbouring region of spacetime. The  fact that only a finite number of parameter are available prevents an arbitrary realignment of the worldlines of material bodies in the  neighbourhood of any given event. 