Covariant Loop Quantum Gravity with a Cosmological Constant

A Lorentzian spinfoam construction incorporates a nonzero cosmological constant into covariant loop quantum gravity using Chern-Simons methods. This seminar reviews the model's finite amplitudes and its connection to general relativity in the classical regime. Stationary-phase techniques provide a framework for calculating physical observables and quantum corrections, with further developments and applications discussed.