The Fock space of loopy spin networks for quantum gravity

  title={The Fock space of loopy spin networks for quantum gravity},
  author={Christoph Charles and Etera R. Livine},
  journal={General Relativity and Gravitation},
In the context of the coarse-graining of loop quantum gravity, we introduce loopy and tagged spin networks, which generalize the standard spin network states to account explicitly for non-trivial curvature and torsion. Both structures relax the closure constraints imposed at the spin network vertices. While tagged spin networks merely carry an extra spin at every vertex encoding the overall closure defect, loopy spin networks allow for an arbitrary number of loops attached to each vertex. These… 
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