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A group field theory for 3d quantum gravity coupled to a scalar field

Laurent Freidel·Daniele Oriti·James Ryan
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Abstract

We present a new group field theory model, generalising the Boulatov model, which incorporates both 3-dimensional gravity and matter coupled to gravity. We show that the Feynman diagram amplitudes of this model are given by Riemannian quantum gravity spin foam amplitudes coupled to a scalar matter field. We briefly discuss the features of this model and its possible generalisations.

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Laurent Freidel, Daniele Oriti, James Ryan. 2005-07-07. A group field theory for 3d quantum gravity coupled to a scalar field. https://arxiv.org/abs/gr-qc/0506067

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