THE EFFECTS OF INHOMOGENEITIES ON EVALUATING THE MASS PARAMETER Ωm AND THE COSMOLOGICAL CONSTANT Λ
نویسنده
چکیده
Analytic expressions for distance–redshift relations which have been corrected for the effects of inhomogeneities in the Friedmann-Lemâ itre-Robertson-Walker (FLRW) mass density are given in terms of Heun functions and are used to illustrate the significance of inhomogeneities on a determination of the mass parameter Ω m and the cosmological constant Λ. The values of these parameters inferred from a given set of observations depend on the fractional amount of matter in inhomogeneities and can significantly differ from those obtained by using the standard magnitude-redshift (m-z) result for pure dust FLRW models. As an example a determination of Ω m made by applying the homogeneous distance–redshift relation to SN 1997ap at z = 0.83 could be as much as 50% lower than its true value. Subject headings: cosmology: theory – large-scale structure of universe – 3 –
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