The infrared triangle in the context of IR safe S matrices

TL;DR

This paper demonstrates that the connections between soft theorems, large gauge transformations, and memories remain valid in infrared safe quantum field theory, offering a simplified and unified understanding rooted in asymptotic dynamics.

Contribution

It provides an improved derivation of large gauge transformation charges, links to classical memory effects, and a more unified treatment within infrared safe quantum field theory.

Findings

Connections persist in infrared safe formulations

Derived charges for large gauge transformations

Unified treatment of soft theorems, memories, and gauge transformations

Abstract

In the present note we show that the recently established connections between soft theorems, large gauge transformations and memories are persistant in the infrared safe formulation of quantum field theory. They take a different and simplified form and can all be derived from the non-trivial asymptotic dynamics that is proper to any theory with massless fields. Several results in this paper had already been presented in one form or another with varying interpretations. The new parts here are an improved derivation of charges for large gauge transformations in the framework of non-trivial asymptotic dynamics, the connection to the classical memory effect and an overall more unified and accessible treatment of the topic. Since the formulation of QFT without infrared divergences is physically more appealing, the infrared safe version of the above connections should be so as well.