Currents for Arbitrary Helicity

TL;DR

This paper challenges a previous claim by constructing a conserved current that couples to massless states of any helicity, including those with |h|>=1, using Mackey's classification.

Contribution

It provides a counterexample to the belief that high-helicity states cannot couple to conserved currents, expanding understanding of massless particle interactions.

Findings

Constructed a conserved current for arbitrary helicity states.

Disproved the claim that |h|>=1 states cannot couple to conserved currents.

Extended the classification of massless representations in quantum field theory.

Abstract

Using Mackey's classification of unitary representations of the Poincar\'e group on massles states of arbitrary helicity we disprove the claim that states with helicity |h|>=1 cannot couple to a conserved current by constructing such a current.