Cosmological perturbation theory at three-loop order
Abstract
We analyze the dark matter power spectrum at three-loop order in standard perturbation theory of large scale structure. We observe that at late times the loop expansion does not converge even for large scales (small momenta) well within the linear regime, but exhibits properties compatible with an asymptotic series. We propose a technique to restore the convergence in the limit of small momentum, and use it to obtain a perturbative expansion with improved convergence for momenta in the range where baryonic acoustic oscillations are present. Our numerical three-loop results are compared with data from N-body simulations at different redshifts, and we find good agreement within this range.
- Publication:
-
Journal of Cosmology and Astroparticle Physics
- Pub Date:
- January 2014
- DOI:
- 10.1088/1475-7516/2014/01/010
- arXiv:
- arXiv:1309.3308
- Bibcode:
- 2014JCAP...01..010B
- Keywords:
-
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- General Relativity and Quantum Cosmology;
- High Energy Physics - Phenomenology
- E-Print:
- 29 pages, 8 figures, 1 table