On the road to percent accuracy: nonlinear reaction of the matter power spectrum to dark energy and modified gravity

Cataneo, Matteo; Lombriser, Lucas; Heymans, Catherine; Mead, Alexander; Barreira, Alexandre; Bose, Sownak; Li, Baojiu

Abstract

We present a general method to compute the nonlinear matter power spectrum for dark energy and modified gravity scenarios with percent-level accuracy. By adopting the halo model and nonlinear perturbation theory, we predict the reaction of a ΛCDM matter power spectrum to the physics of an extended cosmological parameter space. By comparing our predictions to N-body simulations we demonstrate that with no-free parameters we can recover the nonlinear matter power spectrum for a wide range of different w0-wa dark energy models to better than 1% accuracy out to k ≈ 1 h Mpc−1. We obtain a similar performance for both DGP and f(R) gravity, with the nonlinear matter power spectrum predicted to better than 3% accuracy over the same range of scales. When including direct measurements of the halo mass function from the simulations, this accuracy improves to 1%. With a single suite of standard ΛCDM N-body simulations, our methodology provides a direct route to constrain a wide range of non-standard extensions to the concordance cosmology in the high signal-to-noise nonlinear regime.

Citation

Cataneo, M., Lombriser, L., Heymans, C., Mead, A., Barreira, A., Bose, S., & Li, B. (2019). On the road to percent accuracy: nonlinear reaction of the matter power spectrum to dark energy and modified gravity. Monthly Notices of the Royal Astronomical Society, 488(2), 2121-2142. https://doi.org/10.1093/mnras/stz1836

• Journal Article Type: Article
• Acceptance Date: Jun 10, 2019
• Online Publication Date: Jul 4, 2019
• Publication Date: Aug 30, 2019
• Deposit Date: Jun 17, 2019
• Publicly Available Date: Jul 16, 2019
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 488
• Issue: 2
• Pages: 2121-2142
• DOI: https://doi.org/10.1093/mnras/stz1836
• Public URL: https://durham-repository.worktribe.com/output/1299155
• Related Public URLs: https://arxiv.org/abs/1812.05594