Comment on "Limits on the Time Variation of the Electromagnetic Fine-Structure Constant in the Low Energy Limit from Absorption Lines in the Spectra of Distant Quasars"

Abstract

In their Letter [Phys. Rev. Lett. 92, 121302 (2004)] (also [Astron. Astrophys. 417, 853 (2004)]), Srianand et al. analysed optical spectra of heavy-element species in 23 absorption systems along background quasar sight-lines, reporting limits on relative variations in the fine-structure constant: da/a=(-0.06+/-0.06) x 10^{-5}. Here we demonstrate basic flaws in their analysis, using the same data and absorption profile fits, which led to spurious values of da/a and significantly underestimated uncertainties. We conclude that these data and fits offer no stringent test of previous evidence for a varying alpha. In their Reply (arXiv:0711.1742) to this Comment, Srianand et al. state or argue several points regarding their original analysis and our new analysis. We discuss these points here, dismissing all of them because they are demonstrably incorrect or because they rely on a flawed application of simple statistical arguments.

1+2 pages, 1 EPS figure. Page 1 accepted as PRL Comment on arXiv:astro-ph/0402177 . Further details available in arXiv:astro-ph/0612407 . v2: Added critical discussion of Reply from Srianand et al. (arXiv:0711.1742)

Cited by in corpus (9)

• Primordial Nucleosynthesis: from precision cosmology to fundamental physics
• Environmental Dependence of Masses and Coupling Constants
• Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe
• Varying Alpha: New Constraints from Seasonal Variations
• Variation of fundamental constants in space and time: theory and observations
• Eotvos bounds on couplings of fundamental parameters to gravity
• Coulomb energy contribution to the excitation energy in ${}^{229}$Th and enhanced effect of $\alpha$ variation
• Mid- and far-infrared fine-structure line sensitivities to hypothetical variability of the fine-structure constant
• Transition frequency shifts with fine-structure constant variation for Yb II