Résumé / Abstract Seminaire_GReCO

"Quantum gravity and topological quantum field theories with defects"

Marc Geiller
Perimeter Inst. Theoretical Physics (Waterloo, Canada)

In this talk, I will present and explain the structure of vacua underlying the quantum representation and the Hilbert space of loop quantum gravity and related discrete non-perturbative approaches to quantum gravity. This will highlight an unsuspected richness of this class of theories, and make transparent their interpretation as topological quantum field theories with defects. These are theories which posses no local degrees of freedom in the bulk, but can however carry quasi-particle-like excitations on defects of arbitrary co-dimension. Interestingly, such theories have recently attracted lots of attention in condensed matter, where it is believed that they provide a classification of the so-called topologically-ordered phases of matter. On the quantum gravity side, I will explain the relevance of this construction for the study of the continuum limit and of entanglement entropy in gravity and lattice gauge theories.

lundi 9 janvier 2017 - 11:00
Salle des séminaires Évry Schatzman,
Institut d'Astrophysique de Paris

Page web du séminaire / Seminar's webpage