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arXiv · 2409.18889

Dynamical homogenization in effective loop quantum cosmology

Edward Wilson-Ewing
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Abstract

The effective dynamics of loop quantum gravity for marginally bound Lema\^itre-Tolman-Bondi spacetimes predict that the big-bang singularity is resolved and replaced by a cosmic bounce. Numerics show that these effective dynamics also homogenize small regions soon after the bounce when inhomogeneities before the bounce are sufficiently large. These homogeneous regions typically have a width of a few Planck lengths where relative perturbations in the energy density remain less than 15%. If the bounce is followed by an inflationary period, the homogeneous region can reach cosmic scales and the amplitude of relative perturbations can be suppressed to a value compatible with observations.

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Edward Wilson-Ewing. 2024-09-27. Dynamical homogenization in effective loop quantum cosmology. https://doi.org/10.1209/0295-5075%2Fadba0c

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