6 papers
Higher-spin self-dual gravity from holomorphic planes in twistor space
Nicolas Boulanger, Yannick Herfray, Lionel Mason +1
We prove a `nonlinear graviton theorem' for higher-spin self-dual gravity. We consider small deformations of the complex structure of the non-projective twistor space that are boun…
Ti and Spi, Carrollian extended boundaries at timelike and spatial infinity
Jack Borthwick, Maël Chantreau, Yannick Herfray
The goal of this paper is to provide a definition for a notion of extended boundary at time and space-like infinity which, following Figueroa-O'Farril--Have--Prohazka--Salzer, we r…
Infrared physics of QED and gravity from representation theory
Laura Donnay, Yannick Herfray
The infrared structure of QED and gravity is known to be governed by an infinite-dimensional symmetry group which extends the Poincaré group to include, respectively, large …
A geometrical invitation to BMS group theory
Xavier Bekaert, Yannick Herfray, Lea Mele +1
In these lecture notes, a group-theoretical introduction to BMS symmetries is provided in a self-contained manner. More precisely, all definitions and structures are purely based o…
BMS representations for generic supermomentum
Xavier Bekaert, Yannick Herfray
We revisit the classification, and give explicit realisations, of unitary irreducible representations of the BMS group. As compared to McCarthy's seminal work, we make use of a uni…
Carrollian representation from twistor space
Laura Donnay, Laurent Freidel, Yannick Herfray
We construct an explicit realization of the action of the loop algebra on fields at null infinity. This action is directly derived by Penrose transform of the geome…