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arXiv · 1101.3524

The Hamiltonian constraint in 3d Riemannian loop quantum gravity

Valentin Bonzom·Laurent Freidel
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Abstract

We discretize the Hamiltonian scalar constraint of three-dimensional Riemannian gravity on a graph of the loop quantum gravity phase space. This Hamiltonian has a clear interpretation in terms of discrete geometries: it computes the extrinsic curvature from dihedral angles. The Wheeler-DeWitt equation takes the form of difference equations, which are actually recursion relations satisfied by Wigner symbols. On the boundary of a tetrahedron, the Hamiltonian generates the exact recursion relation on the 6j-symbol which comes from the Biedenharn-Elliott (pentagon) identity. This fills the gap between the canonical quantization and the symmetries of the Ponzano-Regge state-sum model for 3d gravity.

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Valentin Bonzom, Laurent Freidel. 2011-08-14. The Hamiltonian constraint in 3d Riemannian loop quantum gravity. https://doi.org/10.1088/0264-9381%2F28%2F19%2F195006

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