syren-halofit: A fast, interpretable, high-precision formula for the $\Lambda$CDM nonlinear matter power spectrum

arXiv:2402.17492v1 Announce Type: cross
Abstract: Rapid and accurate evaluation of the nonlinear matter power spectrum, $P(k)$, as a function of cosmological parameters and redshift is of fundamental importance in cosmology. Analytic approximations provide an interpretable solution, yet current approximations are neither fast nor accurate relative to black-box numerical emulators. We use symbolic regression to obtain simple analytic approximations to the nonlinear scale, $k_\sigma$, the effective spectral index, $n_{\rm eff}$, and the curvature, $C$, which are required for the halofit model. …

abstract arxiv astro-ph.co astro-ph.im box cosmology cs.lg cs.ne current evaluation function importance lambda matter parameters power precision redshift solution spectrum type