Video URL
https://pirsa.org/20120009Torsion cosmology and beyond
APA
Barker, W. (2020). Torsion cosmology and beyond. Perimeter Institute for Theoretical Physics. https://pirsa.org/20120009
MLA
Barker, William. Torsion cosmology and beyond. Perimeter Institute for Theoretical Physics, Dec. 08, 2020, https://pirsa.org/20120009
BibTex
@misc{ scivideos_PIRSA:20120009, doi = {10.48660/20120009}, url = {https://pirsa.org/20120009}, author = {Barker, William}, keywords = {Cosmology}, language = {en}, title = {Torsion cosmology and beyond}, publisher = {Perimeter Institute for Theoretical Physics}, year = {2020}, month = {dec}, note = {PIRSA:20120009 see, \url{https://scivideos.org/index.php/pirsa/20120009}} }
William Barker University of Cambridge
Abstract
Torsion is a popular ingredient in gravity, yet fraught with quantum and classical pathologies. I develop a novel torsion theory, consistent with power-counting and unitarity. The Friedmann equations emerge (with dark energy and radiation), as do pp waves and the Schwarzschild vacuum, all without an Einstein-Hilbert term. I show that cosmology sees torsion as a non-canonical scalar, revealing a rich phenomenology of conformal or waterfall inflatons, and cuscutons. I finally argue that future work will be driven less by toy-models, and more by computer surveys. I advocate Hamiltonian and effective field theory approaches to non-Riemannian geometry in general, relevant to ultraviolet completion and modified gravity alike. Such methods should be oriented towards the ultimate test of gravity: observed cosmological structure.