BMS particles
High Energy Physics - Theory
2025-10-02 v2 General Relativity and Quantum Cosmology
Abstract
We construct wavefunctions for unitary irreducible representations (UIRs) of the Bondi-Metzner-Sachs (BMS) group, i.e. BMS particles, and show that they describe quantum superpositions of (Poincar\'e) particles propagating on inequivalent gravity vacua. This follows from reconsidering McCarthy's classification of BMS group UIRs through a unique, Lorentz-invariant but non-linear, decomposition of supermomenta into hard and soft pieces.
Cite
@article{arxiv.2412.06002,
title = {BMS particles},
author = {Xavier Bekaert and Laura Donnay and Yannick Herfray},
journal= {arXiv preprint arXiv:2412.06002},
year = {2025}
}
Comments
5 pages. v2: PRL published version; typos corrected, supplemental material (1 page) added