Possible time-variability of the fine-structure constant expected from the accelerating universe

TL;DR

This paper models the potential time variation of the fine-structure constant within scalar-tensor theories to interpret recent quasar absorption line measurements, highlighting the precision in parameter determination but challenges in detecting dark energy effects.

Contribution

It provides a theoretical framework for the time-variability of the fine-structure constant and refines parameter estimates within scalar-tensor theories based on observational data.

Findings

Parameters of scalar-tensor theory can be determined more accurately than the universe's acceleration.

The model suggests difficulty in detecting dark energy effects in earlier epochs.

The approach fits recent precise measurements of quasar absorption lines.

Abstract

We present a theoretical calculation on the time-variability of the fine-structure constant to fit the result of the recent precise analysis of the measurement of the QSO absorption lines. We find the parameters and initial values of the scalar-tensor theory to be determined much more accurately than fitting the accelerating universe itself, but leading not to easy detections of the effect on the equation of state of the dark energy in the earlier epochs.