Kinetic field theory: Non-linear cosmic power spectra in the mean-field approximation
| Autor: | Christophe Pixius, Felix Fabis, Carsten Littek, Johannes Dombrowski, Robert Lilow, Elena Kozlikin, Sara Konrad, Matthias Bartelmann |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Physics
Cosmology and Nongalactic Astrophysics (astro-ph.CO) Structure formation 010308 nuclear & particles physics QC1-999 Yukawa potential FOS: Physical sciences General Physics and Astronomy Spectral density Astrophysics::Cosmology and Extragalactic Astrophysics Kinetic energy 01 natural sciences Redshift Computational physics Mean field theory 0103 physical sciences Wavenumber Field theory (psychology) 010306 general physics Astrophysics - Cosmology and Nongalactic Astrophysics |
| Zdroj: | SciPost Physics, Vol 10, Iss 6, p 153 (2021) |
| Popis: | We use the recently developed Kinetic Field Theory (KFT) for cosmic structure formation to show how non-linear power spectra for cosmic density fluctuations can be calculated in a mean-field approximation to the particle interactions. Our main result is a simple, closed and analytic, approximate expression for this power spectrum. This expression has two parameters characterising non-linear structure growth which can be calibrated within KFT itself. Using this self-calibration, the non-linear power spectrum agrees with results obtained from numerical simulations to within typically $\lesssim10\,\%$ up to wave numbers $k\lesssim10\,h\,\mathrm{Mpc}^{-1}$ at redshift $z = 0$. Adjusting the two parameters to optimise agreement with numerical simulations, the relative difference to numerical results shrinks to typically $\lesssim 5\,\%$. As part of the derivation of our mean-field approximation, we show that the effective interaction potential between dark-matter particles relative to Zel'dovich trajectories is sourced by non-linear cosmic density fluctuations only, and is approximately of Yukawa rather than Newtonian shape. 19 pages, 6 figures, to be submitted to SciPost Physics |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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