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Updated: Jul 25, 2026

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The x-ray luminosity-redshift relationship of quasars
1Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139.
Abstract:
Chronometric cosmology provides an excellent fit for the phenomenological x-ray luminosity-redshift relationship for 49 quasars observed by the Einstein satellite. Analysis of the data on the basis of the Friedmann cosmology leads to a correlation of absolute x-ray luminosity with redshift of >0.8, which is increased to approximately 1 in the bright envelope. Although the trend might be ascribed a priori to an observational magnitude bias, it persists after nonparametric, maximum-likelihood removal of this bias.
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