1/L 2 corrected soft photon theorem from a CFT3 Ward identity
Nabamita Banerjee (Indian Institute of Science Education & Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal, Madhya Pradesh, 420 066, India); Karan Fernandes (Center of Astronomy and Gravitation, National Taiwan Normal University, Taipei, 11677, Taiwan); Arpita Mitra (Physics Division, National Center for Theoretical Sciences, Taipei, 10617, Taiwan, Department of Physics, Pohang University of Science and Technology, Pohang, 37673, Korea)
Classical soft theorems applied to probe scattering processes on AdS4 spacetimes predict the existence of perturbative 1/L 2 corrections to the soft photon and soft graviton factors of asymptotically flat spacetimes. In this paper, we establish that the 1/L 2 corrected soft photon theorem can be derived from a large N CFT3 Ward identity. We derive a perturbed soft photon mode operator on a flat spacetime patch in global AdS4 in terms of an integrated expression of the boundary CFT current. Using the same in the CFT3 Ward identity, we recover the 1/L 2 corrected soft photon factor derived from classical soft theorems.
