# A Celestial Matrix Model

### APA

Marteau, C. (2022). A Celestial Matrix Model. Perimeter Institute. https://pirsa.org/22030092

### MLA

Marteau, Charles. A Celestial Matrix Model. Perimeter Institute, Mar. 01, 2022, https://pirsa.org/22030092

### BibTex

@misc{ pirsa_PIRSA:22030092, doi = {10.48660/22030092}, url = {https://pirsa.org/22030092}, author = {Marteau, Charles}, keywords = {Quantum Fields and Strings}, language = {en}, title = {A Celestial Matrix Model}, publisher = {Perimeter Institute}, year = {2022}, month = {mar}, note = {PIRSA:22030092 see, \url{https://pirsa.org}} }

Charles Marteau University of British Columbia

## Abstract

Since the advent of holography, a lot of progress has been made in our understanding of quantum gravity in AdS. However less is known of its flat space counterpart, even though quantum gravity was certainly first formulated in flat space. Various programs have emerged since, like Celestial Holography or Carrollian Holography, both formulated in four and higher dimensions which is the closest to reality but makes the computation of highly quantum quantities difficult. I will present a 2d model of flat space gravity in which these difficulties can be tackled. This model is dubbed the "Cangemi — Jackiw model" after the authors of arXiv:9203056. It is a model of flat space gravity that can be reformulated in terms of a boundary action whose solutions are Rindler patches. I will explain how this “boundary graviton” reformulation gives access to fully quantum Euclidean results. In particular we will compute the exact spectrum of the Bondi Hamiltonian and show that it can be non-perturbatively completed by a matrix model. I will also comment on scrambling in flat space.

Based on “From black holes to baby universes in CGHS gravity” with Victor Godet (https://arxiv.org/abs/2103.13422) and an upcoming paper with Arjun Kar, Lampros Lamprou and Felipe Rosso.

Zoom Link: https://pitp.zoom.us/j/95709808325?pwd=QVdFUFZiTHVvMWlDb211U3kxQ0ZkZz09