Quantum reduction to Bianchi I models in loop quantum gravity

  title={Quantum reduction to Bianchi I models in loop quantum gravity},
  author={Norbert Bodendorfer},
  journal={Physical Review D},
We propose a quantum symmetry reduction of loop quantum gravity to Bianchi I spacetimes. To this end, we choose the diagonal metric gauge for the spatial diffeomorphism constraint at the classical level, leading to an $\mathbb{R}_{\text{Bohr}}$ gauge theory, and quantise the resulting theory via loop quantum gravity methods. Constraints which lead classically to a suitable reduction are imposed at the quantum level. The dynamics of the resulting model turn out to be very simple and manifestly… 

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