Massive to gauge field reduction and gravitational wave zone information

TL;DR

The paper demonstrates that massive Abelian vector fields smoothly transition to their massless gauge counterparts, implying gravitational wave detection does not necessarily exclude long-range gravity, and highlights differences between Abelian and non-Abelian theories.

Contribution

It explicitly shows the smooth massless limit of massive Abelian fields and discusses implications for gravitational wave observations and the physicality of massive non-Abelian theories.

Findings

Massive Abelian fields emit only maximal helicity radiation.

Massive fields mediate Coulomb and Newtonian forces.

Gravitational wave detection does not rule out long-range gravity.

Abstract

We show explicitly that massive, Abelian, vector, just like (properly defined) massive tensor, fields limit smoothly to their massless, gauge, versions: they emit only maximal helicity radiation and mediate Coulomb and (special relativistic) Newtonian, forces between their (conserved) sources. Our main motivation, though, is to show that the recent gravitational wave detection probably cannot directly rule out very long-range gravity: Even though the waves were emitted in a strong field regime, their being detected in the weak field wave zone means the above equivalences apply. There remains the, not unlikely, possibility that no strong field generation of radiation in massive models can reproduce the observed ring-down patterns. Separately, the smooth linear limiting behaviors show that the discontinuity lies not in the mass alone, but rather in Abelian versus non-Abelian, Yang-Mills and General Relativity, regimes, whose respective massive versions are known to be non-physical.