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Further results on geometric operators in quantum gravity

R. Loll
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Abstract

We investigate some properties of geometric operators in canonical quantum gravity in the connection approach à la Ashtekar, which are associated with volume, area and length of spatial regions. We motivate the construction of analogous discretized lattice quantities, compute various quantum commutators of the type [area,volume], [area,length] and [volume,length], and find they are generally non-vanishing. Although our calculations are performed mostly within a lattice-regularized approach, some are -- for special, fixed spin-network configurations -- identical with corresponding continuum computations. Comparison with the structure of the discretized theory leads us to conclude that anomalous commutators may be a general feature of operators constructed along similar lines within a continuum loop representation of quantum general relativity. -- The validity of the lattice approach remains unaffected.

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R. Loll. 1996-12-31. Further results on geometric operators in quantum gravity. https://doi.org/10.1088/0264-9381%2F14%2F7%2F010

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