# Cosmic expansion from spinning black holes

## TL;DR

This paper investigates how a universe with spinning black holes can exhibit cosmological expansion similar to standard models, analyzing the influence of black hole properties on the expansion dynamics.

## Contribution

It introduces a detailed analysis of the expansion in a black hole lattice universe, highlighting the role of black hole spin and mass in mimicking FLRW cosmology.

## Key findings

- Good agreement with matter-dominated FLRW when residual radiation decays
- Effective density matches the horizon mass of black holes
- Black hole spin influences the expansion properties

## Abstract

We examine how cosmological expansion arises in a universe containing a lattice of spinning black holes. We study averaged expansion properties as a function of fundamental properties of the black holes, including the bare mass of the black holes and black hole spin. We then explore how closely the expansion properties correspond to properties of a corresponding matter-dominated FLRW universe. As residual radiation present in the initial data decays, we find good agreement with a matter-dominated FLRW solution, and the effective density in the volume is well-described by the horizon mass of the black hole.