English

Inhomogeneous Cosmology with Numerical Relativity

Cosmology and Nongalactic Astrophysics 2017-03-22 v2 General Relativity and Quantum Cosmology

Abstract

We perform three-dimensional numerical relativity simulations of homogeneous and inhomogeneous expanding spacetimes, with a view towards quantifying non-linear effects from cosmological inhomogeneities. We demonstrate fourth-order convergence with errors less than one part in 10^6 in evolving a flat, dust Friedmann-Lemaitre-Roberston-Walker (FLRW) spacetime using the Einstein Toolkit within the Cactus framework. We also demonstrate agreement to within one part in 10^3 between the numerical relativity solution and the linear solution for density, velocity and metric perturbations in the Hubble flow over a factor of ~350 change in scale factor (redshift). We simulate the growth of linear perturbations into the non-linear regime, where effects such as gravitational slip and tensor perturbations appear. We therefore show that numerical relativity is a viable tool for investigating nonlinear effects in cosmology.

Keywords

Cite

@article{arxiv.1611.05447,
  title  = {Inhomogeneous Cosmology with Numerical Relativity},
  author = {Hayley J. Macpherson and Paul D. Lasky and Daniel J. Price},
  journal= {arXiv preprint arXiv:1611.05447},
  year   = {2017}
}

Comments

12 pages, 10 figures, accepted for publication in Phys. Rev. D

R2 v1 2026-06-22T16:54:50.093Z