Will COBE Challenge the Inflationary Paradigm? Cosmic Microwave Background Anisotropies versus Large-Scale Streaming Motions Revisited
Abstract
The relation between cosmic microwave background (CMB) anisotropies and large-scale galaxy streaming motions is examined within the framework of inflationary cosmology. The minimal Sachs & Wolfe CMB anisotropies at large angular scales in the models with initial Harrison-Zel'dovich spectrum of inhomogeneity normalized to the local large-scale bulk flow, which are independent of the Hubble constant and specific nature of dark matter, are found to be within the anticipated ultimate sensitivity limits of COBE's DMR experiment. For example, the most likely value of the quadrupole coefficient is predicted to be a_2_ >= 7 x 10^-6^, where equality applies to the limiting minimal model. If (1) COBE's DMR instruments perform well throughout the 2 year period, (2) the anisotropy data are not marred by the systematic errors, (3) the large-scale motions retain their present observational status, (4) there is no statistical conspiracy in a sense of the measured bulk flow being of untypically high and the large-scale anisotropy of untypically low amplitudes, and (5) the low- order multipoles in the all-sky primordial fireball temperature map are not detected, the inflationary paradigm will have to be questioned.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1991
- DOI:
- 10.1086/185964
- Bibcode:
- 1991ApJ...370L...5G
- Keywords:
-
- Cosmic Background Explorer Satellite;
- Relic Radiation;
- Anisotropy;
- Astronomical Models;
- Hubble Constant;
- Power Spectra;
- Astrophysics;
- COSMIC BACKGROUND RADIATION;
- COSMOLOGY