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Related papers: COSMOLOGICAL ORIGIN OF QUASARS

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Based on numerical simulations of gas-rich galaxy mergers, we discuss a model in which quasar activity is tied to the self-regulated growth of supermassive black holes in galaxies. Nuclear inflow of gas attending a galaxy collision triggers…

Quasars are associated with and powered by the accretion of material onto massive black holes; the detection of highly luminous quasars with redshifts greater than z = 6 suggests that black holes of up to ten billion solar masses already…

Astrophysics of Galaxies · Physics 2016-04-27 Jens Thomas , Chung-Pei Ma , Nicholas J. McConnell , Jenny E. Greene , John P. Blakeslee , Ryan Janish

Observations of luminous quasars and their supermassive black holes at z~6 suggest that they formed at dense matter peaks in the early universe. However, few studies have found definitive evidence that the quasars lie at cosmic density…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 Roderik A. Overzier

The origin and properties of black hole seeds that grow to produce the detected population of supermassive black holes are unconstrained at present. Despite the existence of several potentially feasible channels for the production of…

After 45 years since the discovery of quantum-gravitational birth of the cosmological density perturbations we can try to answer the main question of cosmology what is the origin of the Universe. This has become possible because the…

General Relativity and Quantum Cosmology · Physics 2025-05-09 Vladimir N. Lukash , Elena V. Mikheeva

The collapse of supermassive primordial stars in hot, atomically-cooled halos may have given birth to the first quasars at $z \sim$ 15 - 20. Recent numerical simulations of these rapidly accreting stars reveal that they are cool, red…

The formation of massive black holes may precede the epoch that characterises the peak of galaxy formation, as characterized by the star formation history in luminous galaxies. Hence protogalactic star formation may be profoundly affected…

Astrophysics · Physics 2011-05-05 Joseph Silk , Martin J. Rees

In this paper we discuss the properties of the quasi-steady state cosmological model (QSSC) developed in 1993 in its role as a cyclic model of the universe driven by a negative energy scalar field. We discuss the origin of such a scalar…

Astrophysics · Physics 2015-05-13 Jayant V. Narlikar , Geoffrey Burbidge , R. G. Vishwakarma

So far, roughly 40 quasars with redshifts greater than z=6 have been discovered. Each quasar contains a black hole with a mass of about one billion solar masses ($10^9 M_\odot$). The existence of such black holes when the Universe was less…

The $\Lambda$-CDM model of cosmology has done much to clarify our picture of the early universe. However, there are still some questions that $\Lambda$-CDM does not necessarily answer; questions such as what is the fundamental nature of…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-17 Wenzer Qin

The existence of supermassive black holes as early as z ~ 7 is one of the great unsolved problems in cosmological structure formation. One leading theory argues that they are born during catastrophic baryon collapse in z ~ 15 protogalaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Daniel J. Whalen , Wesley Even , Joseph Smidt , Alexander Heger , K. -J. Chen , Chris L. Fryer , Massimo Stiavelli , Hao Xu , Candace C. Joggerst

The Universe was nearly smooth and homogeneous before a redshift of z = 100, about 20 million years after the Big Bang. After this epoch, the tiny fluctuations imprinted upon the matter distribution during the initial expansion began to…

Astrophysics · Physics 2009-11-10 Juerg Diemand , Ben Moore , Joachim Stadel

We propose that the majority of quasars at redshift $z\sim 1 - 5$ formed in the environment of new born collapsed halos with 1-D velocity dispersion $\sigma_v^{1d} \sim 400 \kms$. The harboring coefficient $f$ of quasars per halo and the…

Astrophysics · Physics 2009-10-30 Li-Zhi Fang , Y. P. Jing

We investigate the environments of quasars such as number distribution of galaxies using a semi-analytic model which includes both galaxy and quasar formations based on the hierarchical clustering scenario. We assume that a supermassive…

Astrophysics · Physics 2014-12-02 Motohiro Enoki , Masahiro Nagashima , Naoteru Gouda

Supermassive stars, with masses greater than a million solar masses, are possible progenitors of supermassive black holes in galactic nuclei. Because of their short nuclear burning timescales, such objects can be formed only when matter is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Mitchell C. Begelman

Exceptionally bright quasars with redshifts up to z=6.28 have recently been discovered. Quasars are thought to be powered by the accretion of gas onto supermassive black holes at the centres of galaxies. Their maximum (Eddington) luminosity…

Astrophysics · Physics 2015-06-24 Stuart Wyithe , Abraham Loeb

We consider a primordial black hole of very high mass, $10^9-10^{10}M_\odot$, surrounded by dark matter and barionic halo at redshifts $z\sim20$ without any local sources of energy release. Such heavy and concentrated objects in the early…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-09 V. K. Dubrovich , Yu. N. Eroshenko , S. I. Grachev

The James Webb Space Telescope (JWST) has recently uncovered a new record-breaking quasar, UHZ1, at a redshift of $z\sim10$. This discovery continues JWST's trend of confronting the expectations from the standard $\Lambda$CDM model of…

Astrophysics of Galaxies · Physics 2023-12-22 Cosmin Ilie , Katherine Freese , Andreea Petric , Jillian Paulin

Recently, it was suggested that large concentrations or groups of quasars may trace sites of enhanced matter density at medium and high redshifts analogous to how galaxy clusters trace them in nearby space. We have checked existing quasar…

Astrophysics · Physics 2019-04-03 Boris V. Komberg , Andrey V. Kravtsov , Vladimir N. Lukash

Based on the previously formulated theory of spherical perturbations in the cosmological medium of self-gravitating scalarly charged fermions with the Higgs scalar interaction and the similarity properties of such models, the formation of…

General Relativity and Quantum Cosmology · Physics 2024-04-11 Yu. G. Ignat'ev
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