др Дејан Симић

24. октобра 2023.

У оквиру семинара Групе за гравитацију, честице и поља Института за физику у Београду, у петак, 27. октобра 2023. године, у 11 часова у сали 360, др Дејан Симић (Институт за физику у Београду) одржаће предавање:

Note on asymptotic symmetry of massless scalar field at null infinity


Since ten years ago, we have known that the memory effect, soft theorem and asymptotic symmetry at null infinity are mutually equivalent. Any massless field has its soft theorem, including a massless scalar field, so we expect the asymptotic symmetry associated with the massless scalar case to be present also. We will try to understand the asymptotic symmetry of a massless scalar field at null infinity. In order to make sense ofasymptotic symmetry for theory without gauge symmetry, we slightly generalize the notion of asymptotic symmetry. Derivations of the results are done in two different ways, using Hamiltonian analysis and using covariant phase space. Along the way, we will explain the necessary concepts, such as asymptotic symmetry, Hamiltonian analysis and covariant phase space.