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The projector on physical states in loop quantum gravity

Carlo Rovelli
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Abstract

We construct the operator that projects on the physical states in loop quantum gravity. To this aim, we consider a diffeomorphism invariant functional integral over scalar functions. The construction defines a covariant, Feynman-like, spacetime formalism for quantum gravity and relates this theory to the spin foam models. We also discuss how expectation values of physical quantity can be computed.

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Carlo Rovelli. 1998-10-30. The projector on physical states in loop quantum gravity. https://doi.org/10.1103/physrevd.59.104015

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