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arXiv · 1605.00497

Spacetime-noncommutativity regime of Loop Quantum Gravity

Giovanni Amelino-Camelia·Malú Maira da Silva·Michele Ronco·Lorenzo Cesarini·Orchidea Maria Lecian
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Abstract

A recent study by Bojowald and Paily provided a path toward the identification of an effective quantum-spacetime picture of Loop Quantum Gravity, applicable in the "Minkowski regime", the regime where the large-scale (coarse-grained) spacetime metric is flat. A pivotal role in the analysis is played by Loop-Quantum-Gravity-based modifications to the hypersurface deformation algebra, which leave a trace in the Minkowski regime. We here show that the symmetry-algebra results reported by Bojowald and Paily are consistent with a description of spacetime in the Minkowski regime given in terms of the $\kappa$-Minkowski noncommutative spacetime, whose relevance for the study of the quantum-gravity problem had already been proposed for independent reasons.

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Giovanni Amelino-Camelia, Malú Maira da Silva, Michele Ronco, Lorenzo Cesarini, Orchidea Maria Lecian. 2016-05-02. Spacetime-noncommutativity regime of Loop Quantum Gravity. https://doi.org/10.1103/physrevd.95.024028

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