• DOI:10.1038/319751A0
• Corpus ID: 4349689

Large-scale homogeneity of the Universe measured by the microwave background

@article{Mandolesi1986LargescaleHO,
  title={Large-scale homogeneity of the Universe measured by the microwave background},
  author={Nazzareno Mandolesi and Pier Ugo Calzolari and Stefano Cortiglioni and F. Delpino and Giorgio Sironi and P. Inzani and G. Deamici and J. E. Solheim and Lars Berger and Robert B. Partridge and P. L. Martenis and C. H. Sangree and Roland Harvey},
  journal={Nature},
  year={1986},
  volume={319},
  pages={751-753}
}

• N. Mandolesi, P. Calzolari, +10 authors R. Harvey
• Published 1 February 1986
• Physics
• Nature

The isotropy of the cosmic-microwave background is a measure of the homogeneity of the Universe at the epoch of last scattering, conventionally taken to be the epoch of recombination of the primeval plasma at a redshift zs ∼1,000. Here we report measurements of the isotropy at a wavelength of 3 cm. At the 95% confidence level, our results restrict departures from isotropy to < 5–7×10−4 on angular scales of ∼2−10°. The angular scale of our observations is of particular cosmological significance because regions of size ∼1° and above1,2 were not causally connected at the epoch of last scattering, at least in conventional big-bang models. Thus in these models, isotropy on scales \[gsims]1° an be stipulated only as an initial condition. In the new inflationary models3, on the other hand, a causal process to produce large-scale isotropy is included.