Issue |
A&A
Volume 689, September 2024
|
|
---|---|---|
Article Number | A10 | |
Number of page(s) | 5 | |
Section | Cosmology (including clusters of galaxies) | |
DOI | https://doi.org/10.1051/0004-6361/202450835 | |
Published online | 27 August 2024 |
The cosmic timeline implied by the JWST reionization crisis
Department of Physics, The Applied Math Program, and Department of Astronomy, The University of Arizona, Tucson, AZ 85721, USA
Received:
22
May
2024
Accepted:
11
June
2024
Context. JWST’s discovery of well-formed galaxies and supermassive black holes only a few hundred million years after the big bang, and the identification of polycyclic aromatic hydrocarbons (PAHs) at z = 6.71, seriously challenge the timeline predicted by ΛCDM. Moreover, the implied bright UV-irradiation of the early Universe suggests a reionization history much too short to comply with the observed evolution of the hydrogen ionization fraction, xHII(z).
Aims. A recent analysis of reionization after JWST concludes that the ΛCDM timeline simply cannot accommodate the combined JWST-Planck observations even if exotic fixes are introduced to modify the standard reionization model. In this paper, we argue that this so-called ‘photon budget crisis’ is more likely due to flaws in the cosmological model itself. We aim to reanalyze the data in the context of established astrophysics with Rh = ct as the background cosmology, an approach that has already been shown to mitigate the tension created by the too-early appearance of galaxies, quasars and PAHs.
Methods. We employ the standard reionization model using the JWST-measured UV luminosity function in the early Universe and the timeline and physical conditions in both ΛCDM and Rh = ct. The former has already been fully probed and discussed elsewhere, and we here merely redo the calculation to ensure consistency with their pioneering work. We then contrast the predicted reionization histories in these two scenarios and compare them with the data.
Results. We confirm that the reionization history predicted by ΛCDM is in significant tension with the observations, and demonstrate that the latter are instead in excellent agreement with the Rh = ct timeline.
Conclusions. Together, the four anomalies uncovered by JWST, including the newly discovered reionization crisis discussed in this paper, provide strong evidence against the timeline predicted by ΛCDM and in favor of the evolutionary history in Rh = ct.
Key words: cosmic background radiation / cosmology: observations / cosmology: theory / diffuse radiation / early Universe / large-scale structure of Universe
© The Authors 2024
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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