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The thread "Fine Structure Constant Varies With Direction in Space!" was locked because it didn't cite papers published in refereed journals. Actually all of this stuff has been published in refereed journals. The list of references below is cut and pasted from http://en.wikipedia.org/wiki/Fine_structure_constant . Quite a few of the papers are also on arxiv.
My own opinion is that Webb et al. are wrong. Extraordinary claims require extraordinary evidence. Their evidence is statistically significant if you (a) believe their error bars, (b) believe that there were no unidentified systematic errors, and (c) believe that, as claimed by Webb, the Chand group's failure to reproduce the result is due to statistical mistakes by Chand et al., rather than being due to the nonexistence of the purported effect. Even if I believed a, b, and c, I wouldn't consider it statistically significant at the level that would make me believe such an extraordinary claim. It would be interesting to hear whether the Chand group has ever responded to the statistical criticisms. If you buy the idea that the fine structure constant varies over time, then it's actually not much of a leap to believe that it varies spatially as well. If it only varied with time in one frame of reference, it would vary in both time and space in another frame that was moving relative to the first. If it depended on cosmological parameters, I suppose it would be surprising to see an anisotropy that was observable in the frame of our own galaxy, which is more or less moving with the Hubble flow.
J.K. Webb et al. (2001). "Further Evidence for Cosmological Evolution of the Fine Structure Constant". Physical Review Letters 87 (9): 091301. doi:10.1103/PhysRevLett.87.091301. arXiv:astro-ph/0012539. PMID 11531558.
M.T. Murphy, J.K. Webb, V.V. Flambaum (2003). "Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra". Monthly Notices of the Royal Astronomical Society 345: 609. doi:10.1046/j.1365-8711.2003.06970.x.
H. Chand et al. (2004). "Probing the cosmological variation of the fine-structure constant: Results based on VLT-UVES sample". Astron. Astrophys. 417: 853. doi:10.1051/0004-6361:20035701.
R. Srianand et al. (2004). "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". Physical Review Letters 92: 121302. doi:10.1103/PhysRevLett.92.121302.
M.T. Murphy, J. K. Webb, V.V. Flambaum (2007). "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”". Physical Review Letters 99: 239001. doi:10.1103/PhysRevLett.99.239001.
M.T. Murphy, J.K. Webb, V.V. Flambaum (2008). "Revision of VLT/UVES constraints on a varying fine-structure constant". Monthly Notices of the Royal Astronomical Society 384: 1053. doi:10.1111/j.1365-2966.2007.12695.x.
My own opinion is that Webb et al. are wrong. Extraordinary claims require extraordinary evidence. Their evidence is statistically significant if you (a) believe their error bars, (b) believe that there were no unidentified systematic errors, and (c) believe that, as claimed by Webb, the Chand group's failure to reproduce the result is due to statistical mistakes by Chand et al., rather than being due to the nonexistence of the purported effect. Even if I believed a, b, and c, I wouldn't consider it statistically significant at the level that would make me believe such an extraordinary claim. It would be interesting to hear whether the Chand group has ever responded to the statistical criticisms. If you buy the idea that the fine structure constant varies over time, then it's actually not much of a leap to believe that it varies spatially as well. If it only varied with time in one frame of reference, it would vary in both time and space in another frame that was moving relative to the first. If it depended on cosmological parameters, I suppose it would be surprising to see an anisotropy that was observable in the frame of our own galaxy, which is more or less moving with the Hubble flow.
J.K. Webb et al. (2001). "Further Evidence for Cosmological Evolution of the Fine Structure Constant". Physical Review Letters 87 (9): 091301. doi:10.1103/PhysRevLett.87.091301. arXiv:astro-ph/0012539. PMID 11531558.
M.T. Murphy, J.K. Webb, V.V. Flambaum (2003). "Further evidence for a variable fine-structure constant from Keck/HIRES QSO absorption spectra". Monthly Notices of the Royal Astronomical Society 345: 609. doi:10.1046/j.1365-8711.2003.06970.x.
H. Chand et al. (2004). "Probing the cosmological variation of the fine-structure constant: Results based on VLT-UVES sample". Astron. Astrophys. 417: 853. doi:10.1051/0004-6361:20035701.
R. Srianand et al. (2004). "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". Physical Review Letters 92: 121302. doi:10.1103/PhysRevLett.92.121302.
M.T. Murphy, J. K. Webb, V.V. Flambaum (2007). "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”". Physical Review Letters 99: 239001. doi:10.1103/PhysRevLett.99.239001.
M.T. Murphy, J.K. Webb, V.V. Flambaum (2008). "Revision of VLT/UVES constraints on a varying fine-structure constant". Monthly Notices of the Royal Astronomical Society 384: 1053. doi:10.1111/j.1365-2966.2007.12695.x.