3 papers
hep-th2026
GGI lectures on boundary and asymptotic symmetries
Simone Speziale
Support material for lectures at the May '25 Galileo Galilei Institute school on asymptotic symmetries and flat holography. Contains an introduction to Noether theorem for gauge th…
hep-th2025
General covariance and boundary symmetry algebras
Antoine Rignon-Bret, Simone Speziale
In general relativity as well as gauge theories, non-trivial symmetries can appear at boundaries. In the presence of radiation some of the symmetries are not Hamiltonian vector fie…
gr-qc2025
Spatially local energy density of gravitational waves
Antoine Rignon-Bret, Simone Speziale
We propose a new set of BMS charges at null infinity, characterized by a super-translation flux that contains only the `hard' term. This is achieved with a specific corner improvem…