Emergent diffeomorphism invariance in a discrete loop quantum gravity model

@article{Gambini2009EmergentDI,
  title={Emergent diffeomorphism invariance in a discrete loop quantum gravity model},
  author={Rodolfo Gambini and Jorge Pullin},
  journal={Classical and Quantum Gravity},
  year={2009},
  volume={26},
  pages={035002}
}
Several approaches to the dynamics of loop quantum gravity involve discretizing the equations of motion. The resulting discrete theories are known to be problematic since the first-class algebra of constraints of the continuum theory becomes second class upon discretization. If one treats the second-class constraints properly, the resulting theories have very different dynamics and number of degrees of freedom than those of the continuum theory. It is therefore questionable how these theories… 
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