## Video URL

http://pirsa.org/23030085# 4-dimensional covariant Loop Quantum Gravity and complex Chern-Simons theory

### APA

Han, M. (2023). 4-dimensional covariant Loop Quantum Gravity and complex Chern-Simons theory. Perimeter Institute for Theoretical Physics. http://pirsa.org/23030085

### MLA

Han, Muxin. 4-dimensional covariant Loop Quantum Gravity and complex Chern-Simons theory. Perimeter Institute for Theoretical Physics, Mar. 02, 2023, http://pirsa.org/23030085

### BibTex

@misc{ scitalks_PIRSA:23030085, doi = {}, url = {http://pirsa.org/23030085}, author = {Han, Muxin}, keywords = {Quantum Gravity}, language = {en}, title = {4-dimensional covariant Loop Quantum Gravity and complex Chern-Simons theory}, publisher = {Perimeter Institute for Theoretical Physics}, year = {2023}, month = {mar}, note = {PIRSA:23030085 see, \url{https://scivideos.org/PIRSA/23030085}} }

Muxin Han Florida Atlantic University

## Abstract

We present an improved formulation of 4-dimensional Lorentzian spinfoam quantum gravity with cosmological constant. The construction of spinfoam amplitudes uses the state-integral model of PSL(2,C) Chern-Simons theory and the implementation of simplicity constraint. The formulation has 2 key features: (1) spinfoam amplitudes are all finite, and (2) With suitable boundary data, the semiclassical asymptotics of the vertex amplitude has two oscillatory terms, with phase plus or minus the 4-dimensional Lorentzian Regge action with cosmological constant for the constant curvature 4-simplex.

Zoom link: https://pitp.zoom.us/j/92219187641?pwd=RUsvcWo2SHFmVTE3NmxDMUZlVEV2UT09