Theory HEP Seminar

Effective group field theory metric for the universe

Lisa Mickel

University of Sheffield

Group field theory (GFT) is a background independent approach to quantum gravity that exhibits rich phenomenology in the cosmological setting. After introducing the basic premises of GFT and its application to cosmology, we will explore a recent proposal that reconstructs an effective metric directly from the quantum theory. This is achieved by relating metric components to the expectation values of operators that are based on symmetries of the GFT action. The construction relies on a relational coordinate system spanned by four massless scalar fields. As a first application, we will examine the effective metric of a flat FLRW universe with scalar perturbations.