Spatiotemporal Structure and Theory Re-Articulation

Abstract

Abstract The framework for the analysis of symmetry and structure in physical theory allows one to identify explicit heuristics for theory rearticulation. One of the most powerful of these heuristics is the surplusing heuristic which is built from the conversion of invariant to surplus structure within a theory. When applied to the pivotal structure of inertial frames within Newtonian mechanics this heuristic leads directly from Newtonian Mechanics to Barbour–Bertotti theory. In Newtonian Mechanics, inertial frames are invariant under the narrow symmetries of the theory given, under the preliminary stance, by rigid Euclidean transformations but variant under the dynamical transformations given by Galilean boosts. Inertial frames are thus dynamically relative invariant structures of the theory. Implementing the surplusing heuristic means converting structure from invariant to surplus and this is exemplified by the case of moving from Newtonian Mechanics to Barbour–Bertotti theory.