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arXiv:2306.04053astro-ph.CO

Detection of the Cosmological Time Dilation of High Redshift Quasars

Geraint F. Lewis, Brendon J. Brewer

Abstract

A fundamental prediction of relativistic cosmologies is that, due to the expansion of space, observations of the distant cosmos should be time dilated and appear to run slower than events in the local universe. Whilst observations of cosmological supernovae unambiguously display the expected redshift-dependent time dilation, this has not been the case for other distant sources. Here we present the identification of cosmic time dilation in a sample of 190 quasars monitored for over two decades in multiple wavebands by assessing various hypotheses through Bayesian analysis. This detection counters previous claims that observed quasar variability lacked the expected redshift-dependent time dilation. Hence, as well as demonstrating the claim that the lack of the redshift dependence of quasar variability represents a significant challenge to the standard cosmological model, this analysis further indicates that the properties of quasars are consistent with them being truly cosmologically distant sources.

arXiv comments
18 pages, 3 figures. Author version of a manuscript under review at Nature Astronomy
Journal reference
DOI
Subjects
astro-ph.COCosmology and Nongalactic Astrophysics gr-qcGeneral Relativity and Quantum Cosmology

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Linked by 3 identifiable commenters in 5 comments across 3 threads, from Jul 2023 to Aug 2023.

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Discussed in comments3 threads

    • Free research paper: https://arxiv.org/abs/2306.04053

      adrian_bView on HNParent context

    • Your question about pulsars is a good one and I'll answer it first, but the study at the top is about quasars, and I'll address that further below. With one exception all known pulsars are in the Milky Way; they are too intrinsically dim (and obscured by dust, much of which is…

      raattgiftView on HNParent context

    • > I don't have access to the paper https://arxiv.org/abs/2306.04053 Someone usually posts up a preprint in discussions where the original link is a summary put out by one of the authors' institutions' public relations department and published unchanged or made even worse by some…

      raattgiftView on HNParent context

    • > Quasar 'clocks' show the universe was five times slower soon after the Big Bang ... By observing quasars, this time horizon has been rolled back to just a tenth the age of the universe, confirming that the universe appears to speed up as it ages. This seems like an incorrect…

      nopassrecoverView on HNParent context

    • The Nature Astronomy paper linked by The Guardian corresponds with the arXiv version https://arxiv.org/abs/2306.04053 "Whilst this time dilation has been unambiguously detected in the light curves exhibited by cosmologically distant supernovae, the appearance of time dilation in…

      raattgiftView on HNParent context

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