scholarly journals Supermassive black holes in the early Universe

2015 ◽  
Vol 471 (2184) ◽  
pp. 20150449 ◽  
Author(s):  
F. Melia ◽  
T. M. McClintock
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Accretion Rate ◽  
Big Bang ◽  
Supermassive Black Holes ◽  
Active Mass ◽  
Time Compression ◽  
First And Second Generation ◽  
The Big Bang ◽  
Friedmann Robertson Walker

The recent discovery of the ultraluminous quasar SDSS J010013.02+280225.8 at redshift 6.3 has exacerbated the time compression problem implied by the appearance of supermassive black holes only approximately 900 Myr after the big bang, and only approximately 500 Myr beyond the formation of Pop II and III stars. Aside from heralding the onset of cosmic re-ionization, these first and second generation stars could have reasonably produced the approximately 5–20  M ⊙ seeds that eventually grew into z approximately 6–7 quasars. But this process would have taken approximately 900 Myr, a timeline that appears to be at odds with the predictions of Λ CDM without an anomalously high accretion rate, or some exotic creation of approximately 10 5   M ⊙ seeds. There is no evidence of either of these happening in the local Universe. In this paper, we show that a much simpler, more elegant solution to the supermassive black hole anomaly is instead to view this process using the age–redshift relation predicted by the R h = ct Universe, an Friedmann–Robertson–Walker (FRW) cosmology with zero active mass. In this context, cosmic re-ionization lasted from t approximately 883 Myr to approximately 2 Gyr ( 6 ≲ z ≲ 15 ), so approximately 5–20  M ⊙ black hole seeds formed shortly after re-ionization had begun, would have evolved into approximately 10 10   M ⊙ quasars by z approximately 6–7 simply via the standard Eddington-limited accretion rate. The consistency of these observations with the age–redshift relationship predicted by R h = ct supports the existence of dark energy; but not in the form of a cosmological constant.

scholarly journals SCHWARZSCHILD–de SITTER BLACK HOLES IN (4 + 1)-DIMENSIONAL BULK

2007 ◽  
Vol 22 (04) ◽  
pp. 289-296
Author(s):  
METİN ARIK ◽  
DİLEK ÇİFTCİ
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Coordinate Transformation ◽  
Static Solution ◽  
Big Bang ◽  
Brane World ◽  
Warp Factor ◽  
De Sitter ◽  
The Big Bang ◽  
Friedmann Robertson Walker

We construct a static solution for (4 + 1)-dimensional bulk such that the (3 + 1)-dimensional world has a linear warp factor and describes the Schwarzschild–dS4 black hole. For m = 0 this four-dimensional universe and Friedmann–Robertson–Walker universe are related with an explicit coordinate transformation. We emphasize that for linear warp factors the effect of bulk on the brane world shows up as the dS4 background which is favored by the big bang cosmology.

scholarly journals Why did Supermassive Black Holes Already Exist in the Early Universe?

2021 ◽  
Vol 4 (1) ◽  
Keyword(s):  
Black Holes ◽  
Early Universe ◽  
Time Scale ◽  
Cosmic Time ◽  
Big Bang ◽  
Supermassive Black Holes ◽  
Short Time ◽  
The Big Bang

Recent observations show that there are many more and much older black holes than previously known. What is particularly puzzling is that supermassive black holes containing more than a billion solar masses already existed in the very early universe. To date, there is no conclusive explanation for how such gravity monsters could have been created in such a short time after the Big Bang. The "Cosmic Time Hypothesis (CTH)" offers a solution to this problem [1]. According to this hypothesis, the early universe had much more time at its disposal than according to the "present-time scale" and the material-condensing forces were much stronger than now. Therefore, objects with extremely large masses could form in a very short "today-time".

scholarly journals Why Did Supermassive Black Holes Already Exist In The Early Universe?

2020 ◽  
Vol 3 (3) ◽  
Keyword(s):  
Black Holes ◽  
Early Universe ◽  
Time Scale ◽  
Cosmic Time ◽  
Big Bang ◽  
Supermassive Black Holes ◽  
Short Time ◽  
The Big Bang

Recent observations show that there are many more and much older black holes than previously known. What is particularly puzzling is that supermassive black holes containing more than a billion solar masses already existed in the very early universe. To date, there is no conclusive explanation for how such gravity monsters could have been created in such a short time after the Big Bang. The “Cosmic Time Hypothesis (CTH)” offers a solution to this problem [1]. According to this hypothesis, the early universe had much more time at its disposal than according to the “present-time scale” and the material-condensing forces were much stronger than now. Therefore, objects with extremely large masses could form in a very short “todaytime”.

Wallace Leslie William Sargent. 15 February 1935 — 29 October 2012

2015 ◽  
Vol 61 ◽  
pp. 467-483
Author(s):  
Donald Lynden-Bell
Keyword(s):  
Black Holes ◽  
Big Bang ◽  
Supermassive Black Holes ◽  
Cosmological Evolution ◽  
Significant Part ◽  
Look Back ◽  
Large Telescopes ◽  
The Big Bang ◽  
The Universe

Wallace Sargent was an astronomer who used large telescopes to great effect. He concentrated on outstanding problems concerning both the origin of the elements and the cosmological evolution of primordial gas clouds. Despite a mainly theoretical education he became an expert spectroscopist and this enabled him to demonstrate that most helium was not formed in stars but was primordial, formed in the Big Bang. This helped to determine the photon : baryon ratio that emerged from it. He played a significant part in the search for the supermassive black holes that were predicted to be in the centres of many galaxies, as is now established. He is most famous for his systematic work with Alec Boksenberg FRS on the intervening hydrogen clouds seen in absorption in the spectra of distant quasars. From their work it appears that most of the 4% of the Universe (by mass) that is now considered to be in normal atoms or ions has indeed been detected, although it is seen at considerable look-back times.

scholarly journals J1342+0928 supports the timeline in the Rh = ct cosmology

2018 ◽  
Vol 615 ◽  
pp. A113 ◽  
Author(s):  
Fulvio Melia
Keyword(s):  
Black Hole ◽  
Dark Matter ◽  
Cold Dark Matter ◽  
Big Bang ◽  
High Mass ◽  
Local Universe ◽  
Time Compression ◽  
The Standard Model ◽  
Accretion Rates ◽  
The Big Bang

Aims. The discovery of quasar J1342+0928 (z = 7.54) reinforces the time compression problem associated with the premature formation of structure in Λ cold dark matter (ΛCDM). 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⊙ seed, created by a Pop II/III supernova, should have taken at least 820 Myr to grow via Eddington-limited accretion. This failure by ΛCDM constitutes one of its most serious challenges, requiring exotic “fixes”, such as anomalously high accretion rates, or the creation of enormously massive (~ 105 M⊙) 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 Rh = 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 Rh = ct cosmology, a 10 M⊙ seed at z ~ 15 (the start of the Epoch of Reionization at t ~ 878 Myr) would have easily grown into an 8 × 108 M⊙ black hole at z = 7.54 (t ~ 1.65 Gyr) via conventional Eddington-limited accretion.

scholarly journals Origins of Stellar Mass Neutron Black Holes, Supermassive Dark Matter Black Holes and Universe Evolution

2021 ◽  
Author(s):  
Jae-Kwang Hwang
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Dark Matter ◽  
Big Bang ◽  
Stellar Mass ◽  
Intermediate Mass ◽  
Milky Way Galaxy ◽  
Dark Matters ◽  
The Big Bang ◽  
Universe Evolution

The origins of the stellar mass neutron black holes and supermassive dark matter black holes without the singularities are reported based on the 4-D Euclidean space. The neutron black holes with the mass of mBH = 5 – 15 msun are made by the 6-quark merged states (N6q) of two neutrons with the mass (m(N6q) = 10 m(n)) of 9.4 GeV/c2 that gives the black hole mass gap of mBH = 3 – 5 msun. Also, the supermassive black holes with the mass of mSMBH = 106 – 1011 msun are made by the merged 3-D states (J(B1B2B3)3 particles) of the dark matters. The supermassive black hole at the center of the Milky way galaxy has the mass of mSMBH = 4.1 106 msun that is consistent with mSMBH = 2.08 - 6.23 106 msun calculated from the 3-D states (J(B1B2B3)3 particles) of the dark matters with the mass of m(J) = 1.95 1015 eV/c2. In other words, this supports the existence of the B1, B2 and B3 dark matters with the proposed masses. The first dark matter black hole (primary black hole) was created at the big bang. This first dark matter black hole decayed to the supermassive dark matter black holes through the secondary dark matter black holes that are explained by the merged states of the J(B1B2B3)3 particles. The universe evolution is closely connected to the decaying process of the dark matter black holes since the big bang. The dark matter cloud states are proposed at the intermediate mass black hole range of mIMBH = 102 – 105 msun. This can explain why the dark matter black holes are not observed at the intermediate mass black hole range of mIMBH = 102 – 105 msun.

scholarly journals Dark matter heating of gas accreting onto Sgr A*

2019 ◽  
Vol 490 (3) ◽  
pp. 3414-3425 ◽  
Author(s):  
Elizabeth R Bennewitz ◽  
Cristian Gaidau ◽  
Thomas W Baumgarte ◽  
Stuart L Shapiro
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Dark Matter ◽  
Steady State ◽  
Cross Sections ◽  
Accretion Rate ◽  
Supermassive Black Holes ◽  
Galactic Centre ◽  
Appreciable Effect ◽  
Sgr A

ABSTRACT We study effects of heating by dark matter (DM) annihilation on black hole gas accretion. We observe that, for reasonable assumptions about DM densities in spikes around supermassive black holes, as well as DM masses and annihilation cross-sections within the standard WIMP model, heating by DM annihilation may have an appreciable effect on the accretion on to Sgr A* in the Galactic Centre. Motivated by this observation we study the effects of such heating on Bondi accretion, i.e. spherically symmetric, steady-state Newtonian accretion on to a black hole. We consider different adiabatic indices for the gas, and different power-law exponents for the DM density profile. We find that typical transonic solutions with heating have a significantly reduced accretion rate. However, for many plausible parameters, transonic solutions do not exist, suggesting a breakdown of the underlying assumptions of steady-state Bondi accretion. Our findings indicate that heating by DM annihilation may play an important role in the accretion onto supermassive black holes at the centre of galaxies, and may help explain the low accretion rate observed for Sgr A*.

scholarly journals Origins of Stellar Mass Neutron Black Holes, Supermassive Dark Matter Black Holes and Universe Evolution

2021 ◽  
Author(s):  
Jae-Kwang Hwang
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Dark Matter ◽  
Big Bang ◽  
Stellar Mass ◽  
Intermediate Mass ◽  
Milky Way Galaxy ◽  
Dark Matters ◽  
The Big Bang ◽  
Universe Evolution

The origins of the stellar mass neutron black holes and supermassive dark matter black holes without the singularities are reported based on the 4-D Euclidean space. The neutron black holes with the mass of mBH = 5 – 15 msun are made by the 6-quark merged states (N6q) of two neutrons with the mass (m(N6q) = 10 m(n)) of 9.4 GeV/c2 that gives the black hole mass gap of mBH = 3 – 5 msun. Also, the supermassive black holes with the mass of mSMBH = 106 – 1011 msun are made by the merged 3-D states (J(B1B2B3)3 particles) of the dark matters. The supermassive black hole at the center of the Milky way galaxy has the mass of mSMBH = 4.1 106 msun that is consistent with mSMBH = 2.08 - 6.23 106 msun calculated from the 3-D states (J(B1B2B3)3 particles) of the dark matters with the mass of m(J) = 1.95 1015 eV/c2. In other words, this supports the existence of the B1, B2 and B3 dark matters with the proposed masses. The first dark matter black hole (primary black hole) was created at the big bang. This first dark matter black hole decayed to the supermassive dark matter black holes through the secondary dark matter black holes that are explained by the merged states of the J(B1B2B3)3 particles. The universe evolution is closely connected to the decaying process of the dark matter black holes since the big bang. The dark matter cloud states are proposed at the intermediate mass black hole range of mIMBH = 102 – 105 msun. This can explain why the dark matter black holes are not observed at the intermediate mass black hole range of mIMBH = 102 – 105 msun.

scholarly journals Supersonic gas streams enhance the formation of massive black holes in the early universe

Science ◽  
2017 ◽  
Vol 357 (6358) ◽  
pp. 1375-1378 ◽  
Author(s):  
Shingo Hirano ◽  
Takashi Hosokawa ◽  
Naoki Yoshida ◽  
Rolf Kuiper
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Early Universe ◽  
Big Bang ◽  
Cloud Formation ◽  
Massive Black Holes ◽  
Gas Condensation ◽  
Gas Streams ◽  
The Big Bang ◽  
Gas Cloud

The origin of super-massive black holes in the early universe remains poorly understood. Gravitational collapse of a massive primordial gas cloud is a promising initial process, but theoretical studies have difficulty growing the black hole fast enough. We report numerical simulations of early black hole formation starting from realistic cosmological conditions. Supersonic gas motions left over from the Big Bang prevent early gas cloud formation until rapid gas condensation is triggered in a protogalactic halo. A protostar is formed in the dense, turbulent gas cloud, and it grows by sporadic mass accretion until it acquires 34,000 solar masses. The massive star ends its life with a catastrophic collapse to leave a black hole—a promising seed for the formation of a monstrous black hole.

Regimes of mini black hole abandoned to accretion

2018 ◽  
Vol 33 (03) ◽  
pp. 1850024
Author(s):  
Biplab Paik
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Mass Range ◽  
Big Bang ◽  
Energy Consideration ◽  
Age Of The Universe ◽  
Half Power ◽  
The Big Bang ◽  
Mini Black Holes ◽  
The Universe

Being inspired by the Eddington’s idea, along with other auxiliary arguments, it is unveiled that there exist regimes of a black hole that would prohibit accretion of ordinary energy. In explicit words, there exists a lower bound to black hole mass below which matter accretion process does not run for black holes. Not merely the baryonic matter, but, in regimes, also the massless photons could get prohibited from rushing into a black hole. However, unlike the baryon accretion abandoned black hole regime, the mass-regime of a black hole prohibiting accretion of radiation could vary along with its ambient temperature. For example, we discuss that earlier to [Formula: see text] s after the big-bang, as the cosmological temperature of the Universe grew above [Formula: see text] K, the mass range of black hole designating the radiation accretion abandoned regime, had to be in varying state being connected with the instantaneous age of the evolving Universe by an “one half” power law. It happens to be a fact that a black hole holding regimes prohibiting accretion of energy is gigantic by its size in comparison to the Planck length-scale. Hence the emergence of these regimes demands mini black holes for not being viable as profound suckers of energy. Consideration of accretion abandoned regimes could be crucial for constraining or judging the evolution of primordial black holes over the age of the Universe.

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