A precise symbolic emulator of the linear matter power spectrum

arXiv:2311.15865v2 Announce Type: replace-cross
Abstract: Computing the matter power spectrum, $P(k)$, as a function of cosmological parameters can be prohibitively slow in cosmological analyses, hence emulating this calculation is desirable. Previous analytic approximations are insufficiently accurate for modern applications, so black-box, uninterpretable emulators are often used. We utilise an efficient genetic programming based symbolic regression framework to explore the space of potential mathematical expressions which can approximate the power spectrum and $\sigma_8$. We learn the ratio between an existing low-accuracy …

abstract applications arxiv astro-ph.co astro-ph.im box computing cs.lg cs.ne emulator function linear matter modern modern applications parameters power spectrum type