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arXiv · 1803.01119

Effective line elements and black-hole models in canonical (loop) quantum gravity

Martin Bojowald·Suddhasattwa Brahma·Dong-han Yeom
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Abstract

Canonical quantization is often used to suggest new effects in quantum gravity, in the dynamics as well as the structure of space-time. Usually, possible phenomena are first seen in a modified version of the classical dynamics, for instance in an effective Friedmann equation, but there should also be implications for a modified space-time structure. Quantum space-time effects, however, are often ignored in this setting because they are not obvious: they require a careful analysis of gauge transformations and the anomaly problem. It is shown here how modified space-time structures and effective line elements can be derived unambiguously, provided an off-shell anomaly-free system of modified constraints exists. The resulting effective line elements reveal signature change as an inescapable consequence of non-classical gauge transformations in the presence of holonomy modifications. The general framework is then specialized to black-hole models in loop quantum gravity. In contrast to previous studies, a self-consistent space-time structure is taken into account, leading to a new picture of black-hole interiors.

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Martin Bojowald, Suddhasattwa Brahma, Dong-han Yeom. 2018-03-03. Effective line elements and black-hole models in canonical (loop) quantum gravity. https://doi.org/10.1103/physrevd.98.046015

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