Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis

TL;DR

This paper investigates how variations in light quark mass affect nuclear forces and primordial element abundances, providing constraints on quark mass changes during Big Bang nucleosynthesis using chiral perturbation theory and observational data.

Contribution

It offers new calculations of quark mass dependence of nuclear interactions and derives stringent limits on quark mass variation from cosmological observations.

Findings

Derived limits on quark mass variation: δm_q/m_q = 0.02 ± 0.04

Stronger limit when including neutron lifetime: |δm_q/m_q| < 0.009

Improved values for quark mass dependence of meson resonances

Abstract

The quark mass dependences of light element binding energies and nuclear scattering lengths are derived using chiral perturbation theory in combination with non-perturbative methods. In particular, we present new, improved values for the quark mass dependence of meson resonances that enter the nuclear force. A detailed analysis of the theoretical uncertainties arising in this determination is presented. As an application we derive from a comparison of observed and calculated primordial deuterium and helium abundances a stringent limit on the variation of the light quark mass, $\delta m_q/m_q = 0.02 \pm 0.04$. Inclusion of the neutron lifetime modification under the assumption of a variation of the Higgs vacuum expectation value that translates into changing quark, electron, and weak gauge boson masses, leads to a stronger limit, $|\delta m_q/m_q| < 0.009$.