2024/12/10 by Aidan Meador-Woodruff, Dragan Huterer, Meador-Woodruff, Aidan +1 · 1 citation
Computer Science · Social Sciences · #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Multimedia Communication and Technology #Parallel Computing and Optimization Techniques
paper · pdf · doi:10.48550/arxiv.2412.07893
openalex publication_date 2024/12/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Big Bang Nucleosynthesis (BBN), the process of creation of lightest elements in the early universe, is a highly robust, precise, and ultimately successful theory that forms one of the three pillars of the standard hot-Big-Bang cosmological model. Existing theoretical treatments of BBN and the associated computer codes are accurate and flexible, but are typically highly technical and opaque, and not suitable for pedagogical understanding of the BBN. Here we present BBN-simple -- a from-scratch numerical calculation of the lightest element abundances pitched at an advanced undergraduate or beginning graduate level. We review the physics of the early universe relevant for BBN, provide information about the reaction rates, and discuss computational-mathematics background that is essential in setting up a BBN calculation. We calculate the abundances of the principal nuclear species in a standard cosmological model, and find a reasonably good agreement with public precision-level BBN codes.