62 articles – 637 Notices  [english version]
 HAL : in2p3-00152760, version 1
 arXiv : 0705.3892
 Physical Review D 77 (2007) 024009
 Spin foam model from canonical quantization
 (2007)
 We suggest a modification of the Barrett-Crane spin foam model of 4-dimensional Lorentzian general relativity motivated by the canonical quantization. The starting point is Lorentz covariant loop quantum gravity. Its kinematical Hilbert space is found as a space of the so-called projected spin networks. These spin networks are identified with the boundary states of a spin foam model and provide a generalization of the unique Barrette-Crane intertwiner. We propose a way to modify the Barrett-Crane quantization procedure to arrive at this generalization: the $B$ field (bi-vectors) should be promoted not to generators of the gauge algebra, but to their certain projection. The modification is also justified by the canonical analysis of Plebanski formulation. Finally, we compare our construction with other proposals to modify the Barret-Crane model.
 Thème(s) : Physique/Relativité Générale et Cosmologie Quantique
 Mot(s)-clé(s) : Loop quantum gravity – quantum geometry – spin foams – Canonical quantization (gravitation) – Covariant and sum-over-histories quantization (gravitation)
 Lien vers le texte intégral : http://fr.arXiv.org/abs/0705.3892
 in2p3-00152760, version 1 http://hal.in2p3.fr/in2p3-00152760 oai:hal.in2p3.fr:in2p3-00152760 Contributeur : Francoise Duceau <> Soumis le : Jeudi 7 Juin 2007, 15:20:24 Dernière modification le : Mercredi 21 Mai 2008, 18:31:23