Skip to content

Relativistic corrections to the growth of structure in modified gravity

Research output: Contribution to journalArticlepeer-review

We present a method to introduce relativistic corrections including linear dark energy perturbations in Horndeski theory into Newtonian simulations based on the N-body gauge approach. We assume that standard matter species (cold dark matter, baryons, photons and neutrinos) are only gravitationally-coupled with the scalar field and we then use the fact that one can include modified gravity effects as an effective dark energy fluid in the total energy-momentum tensor. In order to compute the scalar field perturbations, as well as the cosmological background and metric perturbations, we use the Einstein-Boltzmann code \hiclass. As an example, we study the impact of relativistic corrections on the matter power spectrum in k-essence, a subclass of Horndeski theory, including the effects of massless and massive neutrinos. For massive neutrinos with $\sum m_{\nu} = 0.1$ eV, the corrections due to relativistic species (photons, neutrinos and dark energy) can introduce a maximum deviation of approximately $7\%$ to the power spectrum at $k \sim 10^{-3} \ \textrm{Mpc}^{-1}$ at $z=0$, for a scalar field with sound speed $c_{s}^{2}\sim 0.013$ during matter domination epoch. Our formalism makes it possible to test beyond $\Lambda$CDM models probed by upcoming large-scale structure surveys on very large scales.
Original languageEnglish
JournalJournal of Cosmology and Astroparticle Physics
Publication statusAccepted for publication - 14 Nov 2020


  • 2006.11019v2

    Rights statement: The embargo end date of 2050 is a temporary measure until we know the publication date. Once we know the publication date the full text of this article will be able to view shortly afterwards.

    Accepted author manuscript (Post-print), 843 KB, PDF document

    Due to publisher’s copyright restrictions, this document is not freely available to download from this website until: 1/01/50

Relations Get citation (various referencing formats)

ID: 23467847