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Consistent discretizations for classical and quantum general relativity

Rodolfo Gambini·Jorge Pullin
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Abstract

We consider discretizations of the Einstein action of general relativity such that the resulting discrete equations of motion form a consistent constrained system. Upon ``spin foam'' quantization of the system, consistency allows a natural way of recovering the correct semi-classical theory. A consistent set of approximations to the Einstein equations could also have implications for numerical relativity and for the construction of approximate classical observables for the theory.

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Rodolfo Gambini, Jorge Pullin. 2001-08-24. Consistent discretizations for classical and quantum general relativity. https://arxiv.org/abs/gr-qc/0108062

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