Fine structure constant variation or spacetime anisotropy?

TL;DR

This paper proposes that the observed variation in the fine structure constant may be explained by spacetime inhomogeneity and anisotropy modeled through Finsler geometry, offering an alternative to the standard interpretation.

Contribution

It introduces a Finsler geometric framework to interpret quasar absorption spectra data, linking spacetime anisotropy to variations in the fine structure constant.

Findings

Redshift deviations in Randers spacetime include monopole and dipole components.

Spacetime anisotropy could account for observed $eta$ variation in quasar spectra.

Finsler geometry provides a novel interpretation of cosmological data.

Abstract

Recent observations on the quasar absorption spectra supply evidence for the variation of the fine structure constant $\alpha$. In this paper, we propose another interpretation of the observational data on the quasar absorption spectra: a scenario with spacetime inhomogeneity and anisotropy. Maybe the spacetime is characterized by the Finsler geometry instead of the Riemann one. The Finsler geometry admits fewer symmetries than the Riemann geometry does. We investigate the Finslerian geodesic equations in the Randers spacetime (a special Finsler spacetime). It is found that the cosmological redshift in this spacetime deviates from the one in general relativity. The modification term to the redshift could be generally revealed as a monopole plus dipole function of spacetime locations and directions. We suggest that this modification corresponds to the spatial monopole and dipole of $\alpha$ variation in the quasar absorption spectra.