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Luminosities of High-Redshift Objects in an Accelerating Universe

Daniel Enstrom·Sverker Fredriksson·Johan Hansson
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Abstract

The results from the Supernova Cosmology Project indicate a relation between cosmic distance and redshift that corresponds to an accelerating Universe, and, as a consequence, the presence of an energy component with negative pressure. This necessitates a re-evaluation of such astrophysical luminosities that have been derived through conventional redshift analyses of, e.g., gamma-ray bursts and quasars. We have calculated corrected luminosity distances within two scenarios; the standard one with a non-zero cosmological constant, and the more recently proposed ``quintessence'', with a slowly evolving energy-density component. We find luminosity corrections from +30 to -40 per cent for redshifts with $z=0 - 10$. This finding implicates that the SCP data do not, by themselves, require a revision of the current, rather qualitative modeling of gamma-ray bursts and quasar properties.

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Daniel Enstrom, Sverker Fredriksson, Johan Hansson. 1999-04-20. Luminosities of High-Redshift Objects in an Accelerating Universe. https://arxiv.org/abs/astro-ph/9904262

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