activity
20242026
collaborators

8 papers

hep-th2026

Gravitational Entropy

Sangmin Choi, Malcolm J. Perry

We formulate the classical gravitational entropy of a horizon as a Noether charge that does not require the notion of a temperature, and which is applicable to horizons that are no…

hep-th2026

Dressed Fock Spaces in Gauge Theory and Gravity

Sangmin Choi, Prahar Mitra

Four-dimensional gauge and gravitational theories exhibit long-range interactions that require asymptotic particles to be dressed by clouds of soft photons and gravitons. Faddeev-K…

hep-th2026

A Holographic Model for Soft Photons and Gravitons in Four Dimensions

Sangmin Choi, Prahar Mitra

We construct a two-dimensional action on the celestial sphere that describes the infrared sector of Abelian gauge and gravitational theories in four dimensions. In particular, we u…

hep-th2026

Long-Range Interactions in Celestial CFT

Sangmin Choi, Ameya Kadhe, Andrea Puhm

Loop corrections in QED and gravity have recently been conjectured to give rise to an infinite tower of logarithmic soft theorems governing the universal low-energy behavior of pho…

hep-th2026

Exact Infrared Triangle in Massless sQED with Long-range Interactions

Sangmin Choi, Ameya Kadhe, Andrea Puhm

The logarithmic soft photon theorem in four spacetime dimensions encodes an infinite-dimensional asymptotic symmetry which acts on massive matter as a divergent superphaserotation.…

hep-th2025

The Classical Super-Phaserotation Infrared Triangle

Sangmin Choi, Alok Laddha, Andrea Puhm

The universality of the logarithmic soft photon theorem in four dimensions can be traced to an infinite-dimensional asymptotic symmetry which acts as a local phase rotation on matt…