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arXiv · 2403.15320

From loop quantum gravity to cosmology: the two-vertex model

Álvaro Cendal·Iñaki Garay·Luis J. Garay
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Abstract

We study the notion of volume and its dynamics in the loop-quantum-gravity truncation known as the two-vertex model. We also show that its U(N)-symmetry reduction provides the old effective dynamics of loop quantum cosmology with an arbitrary perfect barotropic fluid content. A suitable modification of the Poisson bracket structure of the U(N)-symmetric model leads to the loop quantum gravity improved dynamics.

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Álvaro Cendal, Iñaki Garay, Luis J. Garay. 2024-03-22. From loop quantum gravity to cosmology: the two-vertex model. https://doi.org/10.1103/physrevd.109.126011

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