0554627 - FZÚ 2022 RIV GB eng J - Journal Article
Brando, G. - Koyama, K. - Wands, D. - Zumalacárregui, M. - Sawicki, Ignacy - Bellini, E.
Fully relativistic predictions in Horndeski gravity from standard Newtonian N-body simulations.
Journal of Cosmology and Astroparticle Physics. Roč. 9, Sep. (2021), č. článku 024. ISSN 1475-7516. E-ISSN 1475-7516
R&D Projects: GA MŠMT EF15_003/0000437
Grant - others:OP VVV - CoGraDS(XE) CZ.02.1.01/0.0/0.0/15_003/0000437
Institutional support: RVO:68378271
Keywords : Horndeski * Newtonian * N-body * QSA
OECD category: Particles and field physics
Impact factor: 7.280, year: 2021 ; AIS: 1.563, rok: 2021
Method of publishing: Limited access
Result website:
https://doi.org/10.1088/1475-7516/2021/09/024DOI: https://doi.org/10.1088/1475-7516/2021/09/024

The N-body gauge allows the introduction of relativistic effects in Newtonian cosmological simulations. Here we extend this framework to general Horndeski gravity theories, and investigate the relativistic effects that the scalar field introduces in the matter power spectrum at intermediate and large scales. In particular, we show that the kineticity function at these scales enhances the amplitude of the signal of contributions coming from the extra degree of freedom. Using the Quasi-Static Approximation (QSA), we separate modified gravity effects into two parts: one that only affects small-scale physics, and one that is due to relativistic effects. This allows our formalism to be readily implemented in modified gravity N-body codes in a straightforward manner, e.g., relativistic effects can be included as an additional linear density field in simulations.
Permanent Link: http://hdl.handle.net/11104/0329334