3 ms·

The article is so-so. But the physics here is really cool. Essentially, there's growing evidence that the fundamental constants may not be perfectly constant. S

The article is so-so. But the physics here is really cool. Essentially, there's growing evidence that the fundamental constants may not be perfectly constant. See http://arxiv.org/abs/1510.02536 http://arxiv.org/abs/1510.02536 for the gory details.

raattgift 11y ago
Would you really characterize this Wilczynska, Webb, King et al. paper as an argument that there is "growing evidence", rather than (say) that it's a number-crunching argument that the small amount of observations that suggested a dipole variation to Webb et al. (and King et al.) show a \Delta\alpha / \alpha that's close enough to unity that one can cherry pick and say "oh yes, there's a (small) dipole variation" or "oh no, the data is consistent with no variation" ? I prefer their earlier slide deck for gory details (it's mostly based on King et al 2012). https://www.eso.org/sci/meetings/2012/ESOat50/Presentations/Day5/Murphy.pdf https://www.eso.org/sci/meetings/2012/ESOat50/Presentations/... See especially the "Really?" slide (p 27). (The previous "What if it's correct?" slide undersells the impact to the standard cosmology of a violation of isotropy and the consequent erosion of the "must be homogenous at scales > 250 Mly" part of the cosmological principle. Also, "what if atomic physics is really obviously different only very slightly outside the horizon?" feels like a declaration of war against the Copernican principle with precious little evidence, and against pretty good theory that has other lines of evidence backing it (cf. Carroll @ http://www.preposterousuniverse.com/blog/2010/10/18/the-fine-structure-constant-is-probably-constant/ http://www.preposterousuniverse.com/blog/2010/10/18/the-fine... who points to Banks, Dine & Douglas @ http://arxiv.org/abs/hep-ph/0112059 http://arxiv.org/abs/hep-ph/0112059 who in turn point to other work that shows that you probably can't vary \alpha without varying other constants like the m_e and QCD coupling).
- rubidium 11y ago
  Missed this comment until today. Helpful slide-deck and references, thanks! I mean "growing evidence" in the sense that it wasn't even questioned before, and some very early-stage experiments have asked the question. I agree with you that it's still _way_ to early to be making any conclusions, and it all may wash away as the experiments improve.

raattgift 11y ago

Would you really characterize this Wilczynska, Webb, King et al. paper as an argument that there is "growing evidence", rather than (say) that it's a number-crunching argument that the small amount of observations that suggested a dipole variation to Webb et al. (and King et al.) show a \Delta\alpha / \alpha that's close enough to unity that one can cherry pick and say "oh yes, there's a (small) dipole variation" or "oh no, the data is consistent with no variation" ? I prefer their earlier slide deck for gory details (it's mostly based on King et al 2012). https://www.eso.org/sci/meetings/2012/ESOat50/Presentations/Day5/Murphy.pdf https://www.eso.org/sci/meetings/2012/ESOat50/Presentations/... See especially the "Really?" slide (p 27). (The previous "What if it's correct?" slide undersells the impact to the standard cosmology of a violation of isotropy and the consequent erosion of the "must be homogenous at scales > 250 Mly" part of the cosmological principle. Also, "what if atomic physics is really obviously different only very slightly outside the horizon?" feels like a declaration of war against the Copernican principle with precious little evidence, and against pretty good theory that has other lines of evidence backing it (cf. Carroll @ http://www.preposterousuniverse.com/blog/2010/10/18/the-fine-structure-constant-is-probably-constant/ http://www.preposterousuniverse.com/blog/2010/10/18/the-fine... who points to Banks, Dine & Douglas @ http://arxiv.org/abs/hep-ph/0112059 http://arxiv.org/abs/hep-ph/0112059 who in turn point to other work that shows that you probably can't vary \alpha without varying other constants like the m_e and QCD coupling).

rubidium 11y ago
Missed this comment until today. Helpful slide-deck and references, thanks! I mean "growing evidence" in the sense that it wasn't even questioned before, and some very early-stage experiments have asked the question. I agree with you that it's still _way_ to early to be making any conclusions, and it all may wash away as the experiments improve.