# A Lorentzian signature model for quantum general relativity

@article{Barrett2000ALS, title={A Lorentzian signature model for quantum general relativity}, author={John W. Barrett and Louis Crane}, journal={Classical and Quantum Gravity}, year={2000}, volume={17}, pages={3101-3118} }

We give a relativistic spin network model for quantum gravity based on the Lorentz group and its q-deformation, the Quantum Lorentz Algebra.
We propose a combinatorial model for the path integral given by an integral over suitable representations of this algebra. This generalises the state sum models for the case of the four-dimensional rotation group previously studied in gr-qc/9709028.
As a technical tool, formulae for the evaluation of relativistic spin networks for the Lorentz group are…

## 335 Citations

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We present a spin foam formulation of Lorentzian quantum General Relativity. The theory is based on a simple generalization of an Euclidean model defined in terms of a field theory over a group. Its…

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Cosmological deformation of Lorentzian spin foam models

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Integrability for relativistic spin networks

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The evaluation of relativistic spin networks plays a fundamental role in the Barrett-Crane state sum model of Lorentzian quantum gravity in 4 dimensions. A relativistic spin network is a graph…

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