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Author
Melia, FulvioAffiliation
Univ Arizona, Dept Phys, Appl Math ProgramUniv Arizona, Dept Astron
Issue Date
2018-07-24Keywords
cosmology: theorycosmology: observations
early Universe
galaxies: active
quasars: supermassive black holes
Metadata
Show full item recordPublisher
EDP SCIENCES S ACitation
Melia, F. (2018). J1342+ 0928 supports the timeline in the Rh= ct cosmology. Astronomy & Astrophysics, 615, A113; DOI: https://doi.org/10.1051/0004-6361/201832752Journal
ASTRONOMY & ASTROPHYSICSRights
© ESO 2018.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
Aims. The discovery of quasar J1342+0928 (z = 7.54) reinforces the time compression problem associated with the premature formation of structure in A cold dark matter (ACDM). Adopting the Planck parameters, we see this quasar barely 690 Myr after the big bang, no more than several hundred Myr after the transition from Pop III to Pop II star formation. Yet conventional astrophysics would tell us that a 10 M-circle dot seed, created by a Pop II/III supernova, should have taken at least 820 Myr to grow via Eddington-limited accretion. This failure by ACDM constitutes one of its most serious challenges, requiring exotic "fixes", such as anomalously high accretion rates, or the creation of enormously massive (similar to 10(5) M-circle dot) seeds, neither of which is ever seen in the local Universe, or anywhere else for that matter. Indeed, to emphasize this point, J1342+0928 is seen to be accreting at about the Eddington rate, negating any attempt at explaining its unusually high mass due to such exotic means. In this paper, we aim to demonstrate that the discovery of this quasar instead strongly confirms the cosmological timeline predicted by the R-h = Ct Universe. Methods. We assume conventional Eddington-limited accretion and the time versus redshift relation in this model to calculate when a seed needed to start growing as a function of its mass in order to reach the observed mass of J1342+0928 at z = 7.54. Results. Contrary to the tension created in the standard model by the appearance of this massive quasar so early in its history, we find that in the R-h = Ct cosmology, a 10 M-circle dot seed at z similar to 15 (the start of the Epoch of Reionization at t similar to 878 Myr) would have easily grown into an 8 x 10(8) M-circle dot black hole at z = 7.54 (t similar to 1.65 Gyr) via conventional Eddington-limited accretion.Note
Open access journal.ISSN
0004-63611432-0746
Version
Final published versionSponsors
Amherst CollegeAdditional Links
https://www.aanda.org/10.1051/0004-6361/201832752ae974a485f413a2113503eed53cd6c53
10.1051/0004-6361/201832752