Forecasts analysis on varying-$\alpha$ theories from gravitational wave standard sirens

TL;DR

This paper forecasts how future gravitational wave standard siren observations could help detect or constrain potential variations in the fine structure constant, using data from Einstein Telescope, LISA, and current lensing observations.

Contribution

It introduces a method to forecast constraints on the time variation of the fine structure constant using gravitational wave standard sirens and lensing data.

Findings

Future standard sirens can significantly improve constraints on $\\alpha$ variations.

Gravitational wave observations complement existing lensing data.

The methodology enhances the search for fundamental constant variations.

Abstract

Motivated by future gravitational waves observations, we perform forecasts analysis to constrain a possible time variation of the fine structure constant ($\alpha$) within the context of the so-called runaway dilaton model. For this purpose, some gravitational-wave standard sirens mock data within the perspective of Einstein Telescope and LISA mission were considered jointly with current strong gravitational lensing systems observations. We find that future standard sirens observations can also play an important role in the search for possible variations of $\alpha$ within the methodology presented in this work.