We review the effect of the formation of nonlinear structures on the expansion rate, spatial
curvature, and light propagation in the universe, focusing on the possibility that this effect …

Abstract Structure occurs over a vast range of scales in the Universe. Our large-scale
cosmological models are coarse-grained representations of what exists, which have much …

While the use of numerical general relativity for modeling astrophysical phenomena and
compact objects is commonplace, the application to cosmological scenarios is only just …

We perform large-scale cosmological simulations that solve Einstein's equations directly via
numerical relativity. Starting with initial conditions sampled from the cosmic microwave …

We examine the properties of a recently proposed observationally viable alternative to
homogeneous cosmology with smooth dark energy, the timescape cosmology. In the …

The problems of coarse-graining and averaging of inhomogeneous cosmologies, and their
backreaction on average cosmic evolution, are reviewed from a physical viewpoint. A …

We investigate effective equations governing the volume expansion of spatially averaged
portions of inhomogeneous cosmologies in spacetimes filled with an arbitrary fluid. This …

We outline the key steps toward the construction of a physical, fully relativistic cosmology.
The influence of inhomogeneities on the effective evolution history of the Universe is …

We derive the relationship of the redshift and the angular diameter distance to the average
expansion rate for universes which are statistically homogeneous and isotropic and where …

Cosmological backreaction suggests a link between structure formation and the expansion
history of the Universe. In order to quantitatively examine this connection, we dynamically …