Theory Working Group

Effective field theories with non-linearly realised symmetries: from flat space scattering amplitudes to cosmology

by David Stefanyszyn (Groningen University)

Europe/Stockholm
132:028

132:028

Description
In this talk I will outline work I have done over the past 12 months or so on non-linearly realised symmetries in effective field theories both on Lorentz invariant and Lorentz violating backgrounds. I will first discuss the general formalism of the coset construction and inverse Higgs constraints as a tool to construct non-linear realisations of spontaneously broken symmetries. I will then explain how this provides a useful classification of scalar and vector quantum field theories in flat space and outline how these symmetries affect observables I.e. the S-matrix. I will also present a general classification of non-linearly realised symmetries within the effective field theory framework of single clock cosmologies. I will make the talk very pedagogical.