Inflation and the statistics of cosmic microwave background anisotropies: From 1-degree to COBE

Mar, 1993
26 pages
Published in:
  • Astrophys.J. 418 (1993) 535
e-Print:
Report number:
  • CFPA-TH-93-01,
  • YCTP-P44-92

Citations per year

1994200220102018202402468
Abstract: (arXiv)
Cosmic Microwave Background (CMB) anisotropies that result from quantum fluctuations during inflation are explored and the impact of their ``cosmic variance'' on the ability to use existing data to probe inflationary models is studied. We calculate the rms temperature fluctuation, and its cosmic variance, for a number of experiments and for models with primordial power spectra which range from n=12n={1\over 2} to 11. We find: (1) cosmic variance obscures the information which can be extracted, so a comparison of the rms temperature fluctuation on small scales with the COBE result can fix nn to only ±0.2\approx\pm 0.2 at best; (2) measurements of the rms fluctuation on 11^{\circ} scales may not allow one to unambiguously infer the tensor contribution to the COBE anisotropy; (3) comparison of this contribution with the predictions of inflation are ambiguous if the quadrupole anisotropy alone is utilized. We discuss means for minimizing the uncertainty due to cosmic variance in comparisons between experiments.
Note:
  • Revised version
  • LaTeX, 18 pages, 6 figures (PostScript). CfPA-TH-93-01, YCTP-P44-92. (Final version with updated references, to appear in ApJ, Dec.~1, 1993)