The Barbero-Immirzi Field and the Nieh–Yan Topological Invariant By George Shiber Posted on Thursday, October 20, 2016Friday, October 26, 2018 In Loop Quantum Gravity, Math, Mathematical Physics, Mathematics, Physics Barbero-Immirzi Parameter, Hilbert-Palatini Action Why the need for the Barbero-Immirzi field? Let me briefly … Continue reading...