== Heisenberg's principle == 
 The article needs to discuss how a point particle can (indeed must) also be delocalised over an appreciable volume of space, to conform with Heisenberg's principle, and yet this is not a contradiction with its having a "pointlike" nature – i.e. the notion of "pointness" is a bit more sophisticated than just where the particle is. 

 Thus, for example, a photon is a point particle.  But without contradiction, a photon emitted by an electron transitioning from an excited state to a ground state is typically about 106 or 107 wavelengths long   ie of the order of a metre or two long.  Under special conditions, it may be possible to manufacture with an even more narrowly defined frequency.  Spatially, these would be even longer. 

 The "pointness" of the particle is to do with its Green's functions, not the physical space it's spread over.