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Updated: Jul 10, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Loop-quantum-gravity vertex amplitude
Jonathan Engle1, Roberto Pereira, Carlo Rovelli
1Centre de Physique Théorique de Luminy, Case 907, F-13288 Marseille, France, EU.
Abstract:
Spin foam models are hoped to provide the dynamics of loop-quantum gravity. However, the most popular of these, the Barrett-Crane model, does not have the good boundary state space and there are indications that it fails to yield good low-energy n-point functions. We present an alternative dynamics that can be derived as a quantization of a Regge discretization of Euclidean general relativity, where second class constraints are imposed weakly. Its state space matches the SO(3) loop gravity one and it yields an SO(4)-covariant vertex amplitude for Euclidean loop gravity.
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