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Learning about quantum gravity with a couple of nodes
Symmetry, integrability and geometry: methods and applications, Tome 8 (2012) Cet article a éte moissonné depuis la source Math-Net.Ru

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Loop Quantum Gravity provides a natural truncation of the infinite degrees of freedom of gravity, obtained by studying the theory on a given finite graph. We review this procedure and we present the construction of the canonical theory on a simple graph, formed by only two nodes. We review the $\mathrm{U}(N)$ framework, which provides a powerful tool for the canonical study of this model, and a formulation of the system based on spinors. We consider also the covariant theory, which permits to derive the model from a more complex formulation, paying special attention to the cosmological interpretation of the theory.
Keywords: discrete gravity, spinors, spinfoam, quantum cosmology.
Mots-clés : canonical quantization 
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     url = {http://geodesic.mathdoc.fr/item/SIGMA_2012_8_a14/}
}
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Enrique F. Borja; Iñaki Garay; Francesca Vidotto. Learning about quantum gravity with a couple of nodes. Symmetry, integrability and geometry: methods and applications, Tome 8 (2012). http://geodesic.mathdoc.fr/item/SIGMA_2012_8_a14/

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