# Spacetime emergence in group field theory

#### Spacetime emergence in group field theory

- Event time: 1:30pm until 2:30pm
- Event date: 23rd November 2023
- Speaker: Steffen Gielen (University of Sheffield)
- Location: Higgs Centre Seminar Room, Room 4305, James Clerk Maxwell Building (JCMB) (James Clerk Maxwell Building (JCMB)) James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB

### Event details

Title:

Spacetime emergence in group field theory

Abstract:

The failure of a simple perturbative quantisation of general relativity

suggests that quantum gravity is fundamentally non-perturbative, defined

by a path integral or sum over spacetime histories. In some approaches

even the spacetime manifold and its topology are not fixed background

structures but part of the sum: we then have a quantum theory "of, not

on spacetime". I will briefly review one such approach, group field

theory, which can be seen as an extension of matrix and tensor models to

higher dimensions. I will highlight a number of applications to

cosmology, including the derivation of an effective Friedmann equation

(with higher-curvature corrections leading to a bounce) for homogeneous

cosmology, and recent work showing how a spacetime metric can be

extracted from this formalism, paving the way towards a physical

interpretation of many other solutions of the theory.

### About Particle Physics Theory seminars

The Particle Physics Theory seminar is a weekly series of talks reflecting the diverse interests of the group. Topics include analytic and numerical calculations based on the Standard Model of elementary particle physics, theories exploring new physics, as well as more formal developments in gauge theories and gravity..