Seminar

Symmetries, both spacetime and gauge, serve as powerful tools in formulating consistent physical theories. With a brief overview of the role of asymptotic symmetries in scattering processes and infrared physics, I will outline different approaches to these symmetries, focusing mainly on Hamiltonian methods. I will then discuss how the asymptotic symmetry of gravity, namely the BMS symmetry, can be canonically described within the light-cone formulation or Dirac's "front form" approach. I shall address several subtleties that arise when setting up the canonical formulation on a single or on two intersecting null hyperplanes. Finally, I will comment on aspects of the light-cone approach that are relevant to ultra-relativistic or Carrollian physics, which has garnered attention in recent years in the context of flat-space holography.