(Broken) Gauge Symmetries and Constraints in Regge Calculus

Understand

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.