A class of decelerating inhomogeneous cosmological models giving rise to accelerating FLRW universes at large scales

Fuente: arXiv
Saved in:
Bibliographic Details
Main Author: Gomes, Leandro G.
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913021975068672
author Gomes, Leandro G.
author_facet Gomes, Leandro G.
contents In this manuscript, we develop a class of inhomogeneous relativistic cosmological models with the following properties: (i) They contain cosmological observers to whom the spatial geometry and the expansion are homogeneous and isotropic; (ii) Matter behaves closely to dust, as it is formed by an ensemble of massive particles whose number density $4$-vector is conserved and reacts viscously to the local tidal forces; (iii) They generalize the dust FLRW model; (iv) They give rise to effective models on large scales that reproduce the FLRW behaviour with dust and a running dark-energy term, which appears as a backreaction effect from the local gravitational potential; (v) By suitably setting the distribution of energy in the current universe, the effective large-scale equation-of-state parameter can reproduce, in principle, any polynomial on the scale factor whose term of order zero is negative; (vi) The luminous distance observations imply an apparent large-scale acceleration, as the deceleration parameter is negative, while in reality the universe is decelerating.
format Preprint
id arxiv_https___arxiv_org_abs_2603_11377
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A class of decelerating inhomogeneous cosmological models giving rise to accelerating FLRW universes at large scales
Gomes, Leandro G.
General Relativity and Quantum Cosmology
83F05, 83C56
In this manuscript, we develop a class of inhomogeneous relativistic cosmological models with the following properties: (i) They contain cosmological observers to whom the spatial geometry and the expansion are homogeneous and isotropic; (ii) Matter behaves closely to dust, as it is formed by an ensemble of massive particles whose number density $4$-vector is conserved and reacts viscously to the local tidal forces; (iii) They generalize the dust FLRW model; (iv) They give rise to effective models on large scales that reproduce the FLRW behaviour with dust and a running dark-energy term, which appears as a backreaction effect from the local gravitational potential; (v) By suitably setting the distribution of energy in the current universe, the effective large-scale equation-of-state parameter can reproduce, in principle, any polynomial on the scale factor whose term of order zero is negative; (vi) The luminous distance observations imply an apparent large-scale acceleration, as the deceleration parameter is negative, while in reality the universe is decelerating.
title A class of decelerating inhomogeneous cosmological models giving rise to accelerating FLRW universes at large scales
topic General Relativity and Quantum Cosmology
83F05, 83C56
url https://arxiv.org/abs/2603.11377