Effective dark matter power spectra in f(R) gravity

He, J.; Li, B.; Hawken, A.J.

Abstract

Using N-body simulations, we measure the power spectrum of the effective dark matter density field, which is defined through the modified Poisson equation in f(R) cosmologies. We find that, when compared to the conventional dark matter power spectrum, the effective power spectrum deviates more significantly from the ΛCDM model. For models with fR0=−10−4, the deviation can exceed 150%, while the deviation of the conventional matter power spectrum is less than 50%. Even for models with fR0=−10−6, for which the conventional matter power spectrum is very close to the ΛCDM prediction, the effective power spectrum shows sizeable deviations. Our results indicate that traditional analyses based on the dark matter density field may seriously underestimate the impact of f(R) gravity on galaxy clustering. We therefore suggest the use of the effective density field in such studies. In addition, based on our findings, we also discuss several possible methods of making use of the differences between the conventional and effective dark matter power spectra in f(R) gravity to discriminate the theory from the ΛCDM model.

Citation

He, J., Li, B., & Hawken, A. (2015). Effective dark matter power spectra in f(R) gravity. Physical Review D, 92(10), Article 103508. https://doi.org/10.1103/physrevd.92.103508

• Journal Article Type: Article
• Publication Date: Nov 5, 2015
• Deposit Date: Aug 17, 2015
• Publicly Available Date: Nov 12, 2015
• Journal: Physical Review D - Particles, Fields, Gravitation, and Cosmology
• Print ISSN: 1550-7998
• Electronic ISSN: 1550-2368
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 92
• Issue: 10
• Article Number: 103508
• DOI: https://doi.org/10.1103/physrevd.92.103508
• Public URL: https://durham-repository.worktribe.com/output/1424067
• Related Public URLs: http://arxiv.org/abs/1505.03656