Space-time variation of the s and c quark masses

TL;DR

This paper investigates how the masses of strange and charm quarks may vary over space and time in the universe, using data from nuclear and atomic clocks, and discusses potential improvements from future nuclear clock technology.

Contribution

It provides new limits on the variation of s and c quark masses over space and time, incorporating data from multiple sources and considering effects of dark matter fields.

Findings

Limits on s and c quark mass variation from nuclear and atomic clock data.

Potential to improve constraints with 229Th nuclear clock.

Constraints on oscillating dark matter fields affecting quark masses.

Abstract

Space-time variation of fundamental physical constants in expanding Universe is predicted by a number of popular models. The masses of second generation quarks are larger than first generation quark masses by several orders of magnitude, therefore space-time variation in quark masses may significantly vary between each generation. We evaluate limits on variation in the s and c quark masses from Big Bang nucleosynthesis, Oklo natural nuclear reactor, Yb+, Cs and Rb clock data. The construction of 229Th nuclear clock is expected to enhance these limits by several orders of magnitude. Furthermore, constraints are obtained on an oscillating scalar or pseudoscalar cold dark matter field, as interactions of the field with quarks produce variations in quark masses.