Higher-Spin Asymptotic Symmetries, Charges and Soft Theorems

OKC/Nordita High-Energy Physics Theory seminar

Monday 04 February 2019
from 13:15
to 14:00 at
132:028 (Nordita East)

Speaker :

Carlo Heissenberg (Pisa, Scuola Normale Superiore)

Abstract :

Motivated by the link between asymptotic symmetries and soft theorems in four-dimensional gravity and QED, we study the large gauge transformations of massless fields with arbitrary integer spin, in any spacetime dimension.
Upon imposing suitable falloff conditions, analogous to the asymptotic flatness conditions for gravitational systems, we calculate the associated asymptotic charges, the energy flux and, in the Yang-Mills case, the charge flux at null infinity.
In four dimensions, our approach identifies an infinite-dimensional family of higher-spin asymptotic symmetries, whose Ward identities allow us to retrieve the corresponding Weinberg soft theorem.
No such infinite-dimensional asymptotic enhancement seems to occur in higher dimensions, thus leaving the ultimate origin of the soft factorization as an open question.