The Atomic hypothesis: Physical consequences

TL;DR

This paper explores the atomic hypothesis, proposing that elementary particles are indivisible and cannot be excited or modified by interactions, which constrains their mathematical and physical descriptions.

Contribution

It formalizes the atomic hypothesis as a principle that limits the variables and interactions of elementary particles, linking symmetry groups to particle states.

Findings

Elementary particles are indivisible and have no excited states.

Interactions are restricted to minimal coupling forms.

Symmetry groups determine the variables and states of particles.

Abstract

The hypothesis that matter is made of some ultimate and indivisible objects, together the restricted relativity principle, establishes a constraint on the kind of variables we are allowed to use for the variational description of elementary particles. We consider that the atomic hypothesis not only states the indivisibility of elementary particles, but also that these ultimate objects, if not annihilated, cannot be modified by any interaction so that all allowed states of an elementary particle are only kinematical modifications of any one of them. Terefore, an elementary particle cannot have excited states. In this way, the kinematical group of spacetime symmetries not only defines the symmetries of the system, but also the variables in terms of which the mathematical description of the elementary particles can be expressed in either the classical or the quantum mechanical description. When considering the interaction of two Dirac particles, the atomic hypothesis restricts the interaction Lagrangian to a kind of minimal coupling interaction.