TY - JOUR

T1 - Angular correlation of the cosmic microwave background in the R h = ct Universe

AU - Melia, F.

N1 - Funding Information:
This research was partially supported by ONR grant N00014-09-C-0032 at the University of Arizona, and by a Miegunyah Fellowship at the University of Melbourne. I am particularly grateful to Amherst College for its support through a John Woodruff Simpson Lectureship. And I am happy to acknowledge the helpful comments by the anonymous referee, that have led to a significant improvement in this manuscript.

PY - 2014/1

Y1 - 2014/1

N2 - Context. The emergence of several unexpected large-scale features in the cosmic microwave background (CMB) has pointed to possible new physics driving the origin of density fluctuations in the early Universe and their evolution into the large-scale structure we see today. Aims. In this paper, we focus our attention on the possible absence of angular correlation in the CMB anisotropies at angles larger than ~60, and consider whether this feature may be the signature of fluctuations expected in the Rh = ct Universe. Methods. We calculate the CMB angular correlation function for a fluctuation spectrum expected from growth in a Universe whose dynamics is constrained by the equation-of-state p =-ρ/3, where p and ρ are the total pressure and density, respectively. Results. We find that, though the disparity between the predictions of ΛCDM and the WMAP sky may be due to cosmic variance, it may also be due to an absence of inflation. The classic horizon problem does not exist in the Rh = ct Universe, so a period of exponential growth was not necessary in this cosmology in order to account for the general uniformity of the CMB (save for the aforementioned tiny fluctuations of 1 part in 100 000 in the WMAP relic signal). Conclusions. We show that the Rh = ct Universe without inflation can account for the apparent absence in CMB angular correlation at angles θ â‰ 60 without invoking cosmic variance, providing additional motivation for pursuing this cosmology as a viable description of nature.

AB - Context. The emergence of several unexpected large-scale features in the cosmic microwave background (CMB) has pointed to possible new physics driving the origin of density fluctuations in the early Universe and their evolution into the large-scale structure we see today. Aims. In this paper, we focus our attention on the possible absence of angular correlation in the CMB anisotropies at angles larger than ~60, and consider whether this feature may be the signature of fluctuations expected in the Rh = ct Universe. Methods. We calculate the CMB angular correlation function for a fluctuation spectrum expected from growth in a Universe whose dynamics is constrained by the equation-of-state p =-ρ/3, where p and ρ are the total pressure and density, respectively. Results. We find that, though the disparity between the predictions of ΛCDM and the WMAP sky may be due to cosmic variance, it may also be due to an absence of inflation. The classic horizon problem does not exist in the Rh = ct Universe, so a period of exponential growth was not necessary in this cosmology in order to account for the general uniformity of the CMB (save for the aforementioned tiny fluctuations of 1 part in 100 000 in the WMAP relic signal). Conclusions. We show that the Rh = ct Universe without inflation can account for the apparent absence in CMB angular correlation at angles θ â‰ 60 without invoking cosmic variance, providing additional motivation for pursuing this cosmology as a viable description of nature.

KW - Cosmic background radiation

KW - Cosmological parameters

KW - Cosmology: observations

KW - Cosmology: theory

KW - Dark matter

KW - Gravitation

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U2 - 10.1051/0004-6361/201322285

DO - 10.1051/0004-6361/201322285

M3 - Article

AN - SCOPUS:84891698173

SN - 0004-6361

VL - 561

JO - Astronomy and Astrophysics

JF - Astronomy and Astrophysics

M1 - A80

ER -