Bounds on variations of the strange quark mass from Big Bang nucleosynthesis

TL;DR

This paper investigates how variations in the strange quark mass could affect primordial element abundances during Big Bang nucleosynthesis, establishing strict limits on such variations based on observational data.

Contribution

It provides the first quantitative bounds on strange quark mass variations derived from Big Bang nucleosynthesis constraints.

Findings

Deuterium and helium-4 abundances tightly constrain nucleon mass variations.

Upper bound on strange quark mass variation is approximately 5.1%.

Nucleon mass variations significantly impact primordial element synthesis.

Abstract

We analyze the effect of a variation of the strange nucleon matrix element $\langle N| m_s \bar{s}s|N\rangle$ on the abundances of the light elements produced in the Big Bang. For that, we vary the nucleon mass in the leading eight reactions that involve neutrons, protons and the four lightest nuclei. We use various available Big Bang nucleosynthesis codes and find that the measured deuterium and $^4$He abundances set strict limits on the nucleon mass variations. This translates into an upper bound of possible variations of the strange quark mass, $\left| \Delta m_s/m_s \right| \leq 5.1\%$.