English

Two Dimensional Conformal Field Theory from Soft Quantum Electrodynamics in Four Dimensions

High Energy Physics - Theory 2021-10-26 v3 General Relativity and Quantum Cosmology

Abstract

In this work, we propose an effective action of the two-dimensional conformal field theory for the Soft modes appearing in Quantum ElectroDynamics (QED) in 4 dimensions. This is motivated in two ways. First, we motivate the notion of an effective action for the Soft modes using the path integral formalism. Second, by noting the transformations of the on-shell gauge-fixed QED action, we deduce necessary boundary conditions and the corresponding form of the counter-terms that govern the IR sector. We review a derivation of the Soft Ward-Takahashi identity using path integral methods and offer an alternative derivation that follows from the large-gauge variations of the QED action. Because our effective action is that of a conformal theory, we calculate the relevant central charge.

Keywords

Cite

@article{arxiv.2008.03728,
  title  = {Two Dimensional Conformal Field Theory from Soft Quantum Electrodynamics in Four Dimensions},
  author = {Shehab Fadda and Shin'ichi Nojiri},
  journal= {arXiv preprint arXiv:2008.03728},
  year   = {2021}
}

Comments

LaTeX, 14 pages. Totally revised

R2 v1 2026-06-23T17:43:56.833Z