Abstract
THE detection of large-scale inhomogeneities in the Universe has proceeded along a number of fronts. The observed spatial distribution of galaxies indicates clumping of matter on length scales up to ∼30 Mpc (ref. 1). Limits on fine-scale temperature fluctuations in the microwave background2 constrain mass concentrations at the epoch of recombination, and later3,4. Neither of these methods is particularly sensitive to large-scale low-density contrast (δρ/ρ ≪ 1), perturbations at the current epoch (that is, masses ≫ 1019 M⊙ on a scale ≳1,000 Mpc), although in principle the distribution of discrete radio sources on the sky may be investigated for such effects (see for example ref. 5). We show here that measurements of the isotropy of the X-ray background provide a sensitive means of detecting such large-scale inhomogeneities within Z ∼ 5.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Peebles, P. J. E. IAU Symp. 79, 217–225 (1978).
Boynton, P. E. IAU Symp. 79, 317–324 (1978).
Rees, M. J. & Sciama, D. W. Nature 217, 511–516 (1968).
Dyer, C. C. Mon. Not. R. astr. Soc. 175, 429–447 (1976).
Webster, A. Mon. Not. R. astr. Soc. 175, 71–84 (1976).
Peebles, P. J. E. & Wilkinson, D. T. Phys. Rev. 174, 2168 (1968).
Smoot, G. F., Gorenstein, M. V. & Muller, R. A., Phys. Rev. Lett. 39, 898–901 (1977).
Rowan-Robinson, M. & Fabian, A. C. Mon. Not. R. astr. Soc. 170, 199 (1975).
Wolfe, A. M. Astrophys. J. Lett. 159, L61–L67 (1970).
Schwartz, D. Astrophys. J. 162, 439–444 (1970).
Warwick, R. S., Pye, J. P. & Fabian, A. C. (in preparation).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
FABIAN, A., WARWICK, R. On the detection of large-scale inhomogeneities in the Universe. Nature 280, 39–40 (1979). https://doi.org/10.1038/280039a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/280039a0
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.