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arXiv · 1411.0323

Observations on interfacing loop quantum gravity with cosmology

Tomasz Pawłowski
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Abstract

A simple idea of relating the LQG and LQC degrees of freedom is discussed in context of toroidal Bianchi I model. The idea is an expansion of the construction originally introduced by Ashtekar and Wilson-Ewing and relies on explicit averaging of certain sub-class of spin-networks over the subgroup of the diffeomorphisms remaining after the gauge fixing used in homogeneous LQC. It is based on the set of clearly defined principles, thus is a convenient tool to control the emergence and behavior of the cosmological degrees of freedom in studies of dynamics in canonical LQG. Relating the proposed LQG-LQC interface with some results on black hole entropy suggests a modification to the area gap value currently used in LQC.

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Tomasz Pawłowski. 2014-11-02. Observations on interfacing loop quantum gravity with cosmology. https://doi.org/10.1103/physrevd.92.124020

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