Speaker Prof. Garcia-Etxebarria (Durham University (UK))
Talk: "What is a symmetry in physics?"
Abstract: During the last decade or so the idea of “symmetry” in physics has undergone a remarkable evolution from the usual textbook definition — the group of transformations leaving the Lagrangian invariant, a definition that I will review — to a much broader formulation in terms of the “Symmetry TFT”, the embodiment of the symmetries of a theory in terms of an actual physical theory in one dimension higher. I will explain the motivation behind this generalisation, and discuss some consequences and applications of the new formalism.