Cosmological perturbations in the DGP braneworld: numeric solution

TL;DR

This paper introduces a new numerical method to analyze cosmological perturbations in the DGP braneworld model, providing accurate results on large scales for both branches, aiding comparison with observations.

Contribution

A novel numerical approach for solving linear cosmological perturbations in the DGP model without approximations, applicable on large scales.

Findings

Numerical solutions for density perturbations in DGP model.

Comparison framework for DGP predictions and cosmological data.

Analysis of perturbation behavior in both DGP branches.

Abstract

We solve for the behaviour of cosmological perturbations in the Dvali-Gabadadze-Porrati (DGP) braneworld model using a new numerical method. Unlike some other approaches in the literature, our method uses no approximations other than linear theory and is valid on large scales. We examine the behaviour of late-universe density perturbations for both the self-accelerating and normal branches of DGP cosmology. Our numerical results can form the basis of a detailed comparison between the DGP model and cosmological observations.