Abstract
Screen observables, which measure the arrival coordinates of free particles at a hyperplane containing a timelike direction, are defined by a covariance property with respect to an irreducible representation of the Poincaŕe or Galilei group. For each representation with m>0 the set of screen observables is constructed explicitly and a unique ideal screen observable of greatest intrinsic accuracy is singled out.

This publication has 9 references indexed in Scilit: