Can Early Dark Energy Affect Standard Rulers in Cosmology?

[wolram]

Has anyone read this paper?

Shifting the Universe: Early Dark Energy and Standard Rulers
Authors: Eric V. Linder, Georg Robbers
Comments: 6 pages, 3 figures
Subjects: Astrophysics (astro-ph)

The presence of dark energy at high redshift influences both the cosmic sound horizon and the distance to last scattering of the cosmic microwave background. We demonstrate that through the degeneracy in their ratio, early dark energy can lie hidden in the CMB temperature and polarization spectra, leading to an unrecognized shift in the sound horizon. If the sound horizon is then used as a standard ruler, as in baryon acoustic oscillations, then the derived cosmological parameters can be nontrivially biased. Fitting for the absolute ruler scale (just as supernovae must be fit for the absolute candle magnitude) removes the bias but decreases the leverage of the BAO technique by a factor 2.

 

[my_wan]

Link: http://arxiv.org/abs/0803.2877

Submitted two days ago. I did a quick read. My interest in cosmology is fairly limited. What I have learned is geared more as a testing ground for physics. One of the reasons I insist on separating the model from the empirical content. I see nothing really surprising in that paper though.