Constraining spacetime variations of nuclear decay rates from light curves of type Ia supernovae

TL;DR

This paper uses light curves of type Ia supernovae across different redshifts to place constraints on potential spacetime variations in nuclear decay rates, which relate to fundamental constants like the Fermi coupling constant.

Contribution

It provides the first direct bounds on the variation of nuclear decay rates up to redshift z~1 using supernova data.

Findings

Constraints on decay rate variation are not very tight but are the only direct bounds up to z~1.

The results can inform searches for changes in fundamental constants like G_F and v.

The study demonstrates a novel application of supernova light curves to fundamental physics.

Abstract

The luminosity of fading type Ia supernovae is governed by radioactive decays of 56Ni and 56Co. The decay rates are proportional to the Fermi coupling constant G_F and, therefore, are determined by the vacuum expectation value v of the Brout-Englert-Higgs field. We use publicly available sets of light curves of type Ia supernova at various redshifts to constrain possible spacetime variations of the 56Ni decay rate. The resulting constraint is not very tight; however, it is the only direct bound on the variation of the decay rate for redshifts up to z~1. We discuss potential applications of the result to searches for non-constancy of G_F and v.