(Broken) Gauge symmetries and constraints in Regge calculus

@article{Bahr2009BrokenGS,
  title={(Broken) Gauge symmetries and constraints in Regge calculus},
  author={Benjamin Bahr and Bianca Dittrich},
  journal={Classical and Quantum Gravity},
  year={2009},
  volume={26},
  pages={225011}
}
We will examine the issue of diffeomorphism symmetry in simplicial models of (quantum) gravity, in particular for Regge calculus. We find that for a solution with curvature there do not exist exact gauge symmetries on the discrete level. Furthermore, we derive a canonical formulation that exactly matches the dynamics and hence symmetries of the covariant picture. In this canonical formulation broken symmetries lead to the replacements of constraints by so-called pseudo constraints. These… 
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