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arXiv · 2002.04986

Non-covariance of the dressed-metric approach in loop quantum cosmology

Martin Bojowald
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Abstract

The dressed-metric approach is shown to violate general covariance by demonstrating that it cannot have an off-shell completion in which the correct infinitesimal relations of space-time hypersurface deformations are realized. The main underlying reason -- a separation of background degrees of freedom and modes of inhomogeneity that is incompatible with covariance -- is shared with other approaches such as hybrid loop quantum cosmology.

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Martin Bojowald. 2020-02-12. Non-covariance of the dressed-metric approach in loop quantum cosmology. https://doi.org/10.1103/physrevd.102.023532

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