U(N) coherent states for loop quantum gravity

@article{Freidel2011UNCS,
  title={U(N) coherent states for loop quantum gravity},
  author={Laurent Freidel and Etera R. Livine},
  journal={Journal of Mathematical Physics},
  year={2011},
  volume={52},
  pages={052502-052502}
}
We investigate the geometry of the space of N-valent SU(2) intertwiners. We propose a new set of holomorphic operators acting on this space and a new set of coherent states which are covariant under U(N) transformations. These states are labeled by elements of the Grassmannian GrN, 2, they possess a direct geometrical interpretation in terms of framed polyhedra and are shown to be related to the well-known coherent intertwiners. 
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