Part 5 (chapters 5-1 –› 5-4) argues that AGNs may be shrunk galaxies/g-galaxies.

[September 25 2005: Big bang astronomers using the NASA/ESA Hubble Space Telescope have identified the source of a mysterious blue light surrounding a (what they think is a) supermassive black hole in our neighbouring Andromeda Galaxy (M31). The blue light is coming from a disk of hot, young stars. These stars are whipping around the black hole in much the same way as planets in our solar system are revolving around the Sun. The new observations by Hubble's Space Telescope Imaging Spectrograph reveal that the blue light consists of more than 400 stars. The stars are tightly packed in a disk that is only a light-year across. The disk is nested inside an elliptical ring of older, cooler, redder stars, which was seen in previous Hubble observations.
The astronomers are perplexed about how the pancake-shaped disk of stars could form so close to a giant black hole. In such a hostile environment, the black hole's tidal forces should tear matter apart, making it difficult for gas and dust to collapse and form stars. By finding the disk of stars, astronomers also have collected what they say is ironclad evidence for the existence of a monster black hole. The evidence has helped astronomers to rule out all alternative theories for the dark mass in the Andromeda Galaxy's core, they say. The big bang astronomers claim that they are sure they are not dealing with dark clusters of dead stars instead of a black hole. They say their observations are so precise that they eliminated all other possibilities for what the central, dark object could be. They also calculated that the black hole's mass is 140 million Suns, which is three times more massive than once thought. “Andromeda is the first galaxy in which we can exclude all exotic alternatives to a black hole,” they say. “But now that we have proven that the black hole is at the centre of the disk of blue stars, the formation of these stars becomes hard to understand. Gas that might form stars must spin around the black hole so quickly - and so much more quickly near the black hole than farther out - that star formation looks almost impossible. But the stars are there.”³⁷⁰.
Big bang researchers think in times of 14 billion years. If you think of an infinite universe then many darkened stars may have approached each other very slowly over hundreds of billions of years. In that case you will get very different calculations where it comes to clusters of dark stars (many more small stars packed in a very small volume of space). On this website it is suggested that there may be remnants of very old shrunken galaxies in the centers of galaxies (4-1).
Perhaps there is a very old spiral galaxy (or very old cluster of galaxies) in the center of the Andromeda Galaxy, which then may account for the disks with (blue and red) stars: left overs of old spiral arms. Another possibility is that the disk(s) of stars came into existence with stars-swinging-themselves-around-a-big-central-mass, as mentioned on this website when it comes to solar system formation (but then with planets instead of stars, 7-1). End September 25 2005]

[January 23 2006: Researchers have found that a certain type of X-ray explosion common on neutron stars is never seen around their black hole cousins, as if the gas that fuels these explosions has vanished into a void. This is strong evidence, the researchers say, for the existence of a theoretical border around a black hole called an event horizon, a point from beyond which nothing, not even light, can escape³⁹².
There may be a good reason that a certain type of X-ray explosion common on neutron stars is never seen around what (by big bang astronomers) is expected to be a black hole. Perhaps the researched objects that are supposed to be black holes consist of many relatively small dark matter objects circling around each other. In that case much gas can be transported to the many objects before anything shows up in the form of light.

When new physics come to the front, like the (in my opinion) unavoidable pushing gravity (3-2), then theoretical objects that are now taken for granted by conventional scientists, like black holes, neutron stars and white dwarfs, have to be re-calculated. It then may turn out that some (perhaps all) of those objects, i.e. black holes, neutron stars and white dwarfs, are not theoretical possible within the new physics. But of course, I can't say what will be the outcome of such new calculations. Perhaps that also with pushing gravity one may get objects having such strong gravity that light can not escape the object. I don't see it as likely, but I certainly can't predict the outcome of the (in my opinion) unavoidable re-calculation of black holes (and neutron stars and white dwarfs), I have to admit that. End January 23 2006]

Observations of Seyferts seem to reveal that the kinematic centers of AGNs are at the centers of the AGNs, which is, of course, easy to understand with a rotating universal engine at the very core of an AGN.

Perhaps massive (heavy element) dark matter objects get heated by gravitational contraction, which then may produce thermal blackbody optical/UV/X/gamma-rays coming from the central source of AGNs (which then, of course, makes those “dark” matter objects not dark at all anymore).
And: hydrogen gas, attracted by the universal engine from intergalactic space (4-1), may fall towards the universal engine which then will cause starbursts, producing optical/UV/X-ray radiation in a nuclear bulge or a disk (5-1) surrounding the very core of the universal engine (hydrogen may not fall into the very core (= central source/continuum source) of the universal engine because of radiation pressure by the “big ball”, 5-1).
[March 27 2006: Recent work by big bang astronomers points out that inflow of gas into the central region of a galaxy or merging galaxies may cause a quasar (in the center of a host galaxy) to be born. Later the quasar phase may end because a lot of gas has been blown out of the galaxy again causing the galaxy to settle down to a relatively quiet non-AGN-life⁴¹⁰. Such way of looking at AGN-formation is described throughout this webpage. End March 27 2006]

The starburst-AGN connection of Terlevich and collaborators⁴³ has two problems: accounting for rapid X-ray variability and radio-loud activity. My AGN model has a central object, thus my model comes close to the hybrid model: a starburst-connection with a central source (i.e. universal engine core, not a black hole). A universal engine core as a central source may account for high-energy radiation (5-1), X-ray variability (5-1), a BLR region (5-1) and radio loudness (5-2).
[February 2004: Perhaps there is also a possibility that AGNs can come to existence without a galaxy as a progenitor (3-2). End February 2004]

Many scientists think that there is a black hole in the galactic nucleus of the Milky Way, especially concerning Sagittarius A*.
Recent observations with X-ray and radio waves have pointed out that radio source Sagittarius A* has 2.6 x 10⁶ sun masses²²⁹ in a sphere with a diameter of 1 AU. If all this mass would be present in dark matter masses of Earth magnitude (= 6 x 10²⁴ kg) then we get 8.7 x 10¹¹ dark matter objects of Earth-magnitude in a sphere with a diameter of 1 AU. This means that for every “earth” there is a “sphere of space” with a radius of 15,600 km.
With the Earth having a radius of 6,387 km, this would mean that 93% of the space within Sagittarius A* is empty space, which literally may mean: enough space for rotating dark matter, i.e. there is space for a universal engine as described in 4-1 with many dark matter objects rotating around a central point.
(The densities in our Earth are relatively low, as is the mass magnitude of our Earth. Much larger dark matter objects thus will have more “space” in the above mentioned “Sag A* sphere”.)

Of course, in order to have an engine that can give the enormous power that is able to structure our (spiral-shaped) Galaxy (4-3) one way or the other there must be things of an amazing magnitude, like mass of magnitude 2.6 million MSun in a sphere with a diameter of 1 AU. [July 2004: Though, it remains to be seen how much the center of a galaxy shapes the stars in the galaxy directly by gravitational forces and how much the spiral is shaped by gas that rotates in a disk by gravitational forces (caused by a rotating center, 4-3). End July 2004]
With all kind of dark matter masses with all kind of orbiting speeds there will be a lot of clashing between dark matter objects, which may explain the huge amounts of dust in the galactic nucleus. But also: supernovae in the galactic nucleus will cause dust, and outboard dust may have been attracted from outside the galactic nucleus by the universal engine; and inboard dust from supernovae and clashing dark matter objects (outside the galactic nucleus) may have been sucked into the galactic nucleus from within the Galaxy (4-4).
Dust may cause polarization of light coming from the galactic nucleus as well as infrared radiation. Large groups of dark matter objects orbiting the very core of the galactic nucleus may cause variability by obscuration and microlensing (5-1) and they may cause microwave radiation by black body radiation (5-1).

Hydrogen may fall into the universal engine (4-3) and fall on (smaller and cold) dark matter objects, thus bringing O and OB stars and hot coronal gasses. HII and electrons may bring thermal bremsstrahlung and synchrotron radiation (sources that dominate radio maps of the overall galactic center region appear, when investigated at different wavelengths, to have characteristics of HII regions⁸).

[January 24 2006: It is a problem for big bang astronomers how stars can form so efficiently in a place like the galactic center, because it is hard for them to see how stars are still able to form in an environment with unusually strong magnetic fields and tidal shear forces³⁹⁴.
If our galactic center once was an old cluster of galaxies (4-1) then a lot of old darkened stars are around in the galactic center, or/and if our galaxy is much older than expected because it once was an elliptical galaxy (4-3) then a lot of old darkened stars of the old elliptical may be in the center of the galaxy. Such old remnants of stars may attract gas by gravity (7-1), thus forming new stars. End January 24 2006]

Thus, it may not be surprising that all kind of radiation comes from the nucleus of our Galaxy, like thermal and nonthermal radio continuum emission, infrared radiation, X-rays and even gamma rays⁸.
Thus, taking the galactic nucleus of our Galaxy as a laboratory for finding out about AGN activity may bring us (a great deal of) the mechanisms that makes AGNs so bright in all kind of wavelengths, from gamma radiation to radio radiation.
High-energy radiation by gravitational contraction of huge compact heavy element objects (“dark” objects) may be something taking place on a very small scale in our galactic nucleus relative to AGNs (5-1).

The X-ray emission from the nucleus of our Galaxy is expected to come from hot coronal gasses by thermal bremsstrahlung and gamma rays are expected to be caused by electron-positron annihilation. Conventional science considers both ways of radiation production to be possibly at work in AGNs⁴³, though the origin of X-ray and gamma ray emission in AGNs is not understood⁴³.
But perhaps it remains to be seen whether the explanations of X-rays and gamma rays coming from the galactic nucleus are right (5-1).

The X-ray map from the galactic center can roughly be seen as a circle, but this circle consists of discrete sources. If we would see our Galaxy from further away then perhaps these discrete sources would have been thought to be one source. The radiation coming from AGNs may come from many discrete sources with different temperatures, thus spectra can be flat and of a non-black body type, while the radiation is thermal black body radiation (5-1).

Right now X-ray sources in the galactic nucleus are suggested by conventional science to be due to hot coronal gasses. Could those sources be heated up dark matter? If the nucleus of our Galaxy contains an old g-galaxy then there must be many old and massive dark matter objects in the galactic nucleus, which may be heated up strongly by gravitational contraction, which thus may account for (part of the) X-ray radiation as well as (part of the) gamma radiation coming from the galactic nucleus.
Though: there is no BRL (see hereafter) in the galactic nucleus, thus hydrogen can fall into the nucleus and thus all dark matter objects may have assembled hydrogen (though, perhaps not if hydrogen is kept away from the glowing “dark” matter objects by radiation pressure). Thus glowing of dark matter objects by gravitational contraction may not be likely and X-ray emission indeed may rather come from hot gas heated by stars.
But: certain stars may have very big heavy metal cores that can contract a thin layer of gas surrounding the big heavy metal core very strongly. Thus white dwarfs may be stars with a big heavy metal core that fuse gas in a relatively thin layer. A thin layer will produce a much higher temperature at the surface of such a star (6-2, 6-2).
[June 2004: Recently ESA's Integral gamma-ray observatory has resolved the diffuse glow of gamma rays in the center of our Galaxy and has shown that most of it is produced by a hundred individual sources. Integral's gamma-ray telescope IBIS has seen clearly that, instead of a fog produced by the interstellar medium, most of the gamma-rays are coming from individual celestial objects. For more than thirty years, other telescopes had seen nothing but a mysterious, blurry fog of gamma rays. The discovery of 91 gamma-ray sources towards the direction of the Galactic centre therefore was reported. Much to the big bang astronomers surprise, almost half of these sources do not fall in any class of known gamma-ray objects. They are thought to represent a new population of gamma-ray emitters¹³¹.

More recent research once again points out that the galactic center of our Milky Way may be an excellent road to gain good understanding when it comes to AGNs. A long look by NASA's Chandra X-ray Observatory has revealed new evidence that extremely hot gas exists in a large region at the center of the Milky Way. The intensity and spectrum of the high-energy X-rays produced by this gas present a puzzle as to how it is being heated¹⁹¹. The discovery came to light as a team of astronomers, led by Michael Muno of UCLA used Chandra's unique resolving power to study a region about 100 light years across and painstakingly remove the contributions from 2,357 point-like X-ray sources due to white dwarfs, foreground stars, background galaxies and, what they see as, neutron stars and black holes (both neutron stars and black holes may be theoretical outgrowths of relativity and a misunderstanding of gravity, 5-1). What remained was an irregular, diffuse glow from a 10-million-degree Celsius gas cloud, embedded in a glow of higher-energy X-rays with a spectrum characteristic of 100-million-degree gas. They think that the best explanation for the Chandra data is that the high-energy X-rays come from an extremely hot gas cloud, which, according to the team, brings significant shortcoming in understanding of heat sources in the center of our Galaxy (where it comes to big bang cosmology), the source of the heating remains a puzzle. The high-energy diffuse X-rays from the center of the Galaxy appear to be the brightest part of a ridge of X-ray emission observed by Chandra and previous X-ray observatories to extend for several thousand light years along the disk of the Galaxy. The extent of this hot ridge implies that it is probably not being heated by the supermassive black hole at the center of the Milky Way.
Big bang scientists have speculated that magnetic turbulence produced by supernova shock waves can heat the gas to 100 million degrees. Alternatively, high-energy protons and electrons produced by supernova shock waves could be the heat source. However, both these possibilities have problems big bang astronomers agree. They say that the spectrum is not consistent with heating by high-energy particles, the observed magnetic field in the Galactic center does not have the proper structure, and the rate of supernova explosions does not appear to be frequent enough to provide the necessary heating.
The big bang team also considered whether the high-energy X-rays only appear to be diffuse, and are in fact due to the combined glow of an as yet undetected population of point-like sources, like the diffuse lights of a city seen at a great distance. The difficulty with this explanation is that 200,000 sources would be required in the observed region. Although the total number of stars in this region is about 30 million, the number of stars of the type expected to produce X-rays at the required power and energy is estimated to be only 20 thousand. Further, such a large unresolved population of sources would produce a much smoother X-ray glow than is observed. The team says that there is no known class of objects that could account for such a large number of high-energy X-ray sources at the Galactic center¹⁹¹.

I think that celestial objects with a high percentage of dark matter (i.e. with a high amount of (very) heavy elements in the core of the objects) may cause such objects to have high temperatures responsible for high energy rays.
Perhaps that such very hot objects can be (some sort of) pulsars with an extremely short pulse time. For instance, Cygnus X-1, a strong X-ray source, flickers rapidly, in less than 0.001 second. Perhaps that objects with a very fast pulsar mechanism can be the gamma-ray/X-ray sources in the center of our Galaxy (6-1). Perhaps there is also the possibility that objects can be heated by gravitational contraction without a pulsar mechanism (i.e. without an endothermic reaction), thus bringing very hot celestial objects (5-1).
With shrunken concentrated old galaxies in the center of major galaxies one may expect to find many “dark” (merged) matter objects in those centers, which thus may account for (observed) X-ray/gamma-ray sources in the center of our Galaxy.

Though, “dark” (merged) matter objects can be found in all kind of galaxies when stars in galaxies come to existence because gas assembles around (old) dark matter objects (7-1). Therefore it may not be surprising that X-ray sources are found in various locations in elliptical as well as spiral galaxies¹³⁵ (which are a puzzle for big bang astronomers).
When such X-ray objects indeed are due to “dark” (merged) matter objects then they should be found too in certain (very) old (nonluminous) g-galaxies, which is something that may be confirmed one day: X-ray sources in intergalactic/intercluster space (i.e. in nonluminous g-galaxies). End June 2004]

[January 2005: To peer into the galactic center astronomers have used the 6.5-meter-diameter Magellan Telescope in Chile. By gathering infrared light that more easily penetrates dust, the astronomers were able to detect thousands of stars that otherwise would have remained hidden. Their goal was to identify stars that orbit, and feed, X-ray-emitting white dwarfs, neutron stars or black holes - any of which could yield the faint X-ray sources discovered originally with NASA's Chandra X-ray Observatory. Chandra previously detected more than 2000 X-ray sources in the central 75 light-years of our galaxy. About four-fifths of the sources emitted mostly hard (high-energy) X-rays. The precise nature of those hard X-ray sources remained a mystery. Two possibilities were suggested by big bang astronomers: 1) high-mass X-ray binary systems, containing a neutron star or black hole with a massive stellar companion; or, 2) cataclysmic variables, containing a highly magnetized white dwarf with a low-mass stellar companion.
The astronomers now have found that the galactic center Chandra sources are probably low-mass binaries. Since by far the most common low-mass binaries with X-ray luminosities, spectra, and variability similar to the galactic center Chandra sources are accreting magnetic white dwarfs, the astronomers conclude white dwarfs are the most likely identification²⁶⁹.
Thus, my previous suggestion (5-1) that the X-ray sources in our galactic center may be white dwarfs (because our galactic center may be likely to contain a lot of old remnants of stars, i.e. dark matter objects, that get fuelled with gas flowing to the galactic center) may be right. Though, another possibility may be celestial objects (bigger/heavier than white dwarfs) with a high percentage of dark matter (i.e. with a high amount of (very) heavy elements in the core of the objects) may cause such objects to have high temperatures responsible for high energy rays (5-1, 5-1). End January 2005]

The majority of the larger spiral galaxies radiate in the radio continuum⁸, which may be due to larger spirals having stronger universal engines that are more likely to be capable of AGN activity.

One may wonder why there is so little AGN activity in the nucleus of our Galaxy. Perhaps this can be (partly) explained by gravitational shielding (3-2, 5-1) by all the matter surrounding the nucleus (and “pulling” at the nucleus). Once a lot of matter is radiated away (by nuclear processes) contraction of the nucleus may speed up, which may trigger stronger AGN activity.

A big ball (which often may be a little oval) of “dark” matter objects/stars, with (most) merging taking place in the core, may explain why hotter and hotter radiation is found when going from the outside of the AGN nucleus, i.e. big ball/“compact” source, to the inside: if massive dark matter objects contract strongly by gravity and thus start glowing at (extremely) high temperatures, or: if massive dark matter objects have a thin layer of gas that contracts strong enough to fuse into higher elements (5-1).

Perhaps that temperatures raised by gravitational contraction of dark matter objects can go up to 10¹⁰ K or even higher (5-2) if no or little hydrogen surrounds the dark matter objects. Hydrogen may be radiated away from the “big ball” by radiation pressure, see hereafter at The Broad-Line Region (5-1).
Thus gravitational contraction may cause enormous fluxes of high-energy thermal black body radiation (UV, X-ray and gamma ray).
[February 2004: Though, big objects with big heavy element cores may bring different fusion processes (7-1), which may bring very high (surface) temperatures. Surface temperatures of objects may also become very high when fusion processes take place in an object with a big heavy element core and a relatively thin gas mantle (6-2).
A hot extremely bright X-ray object has been observed in the spiral galaxy NGC 1637⁸⁰, which may be hot because of a so far unknown fusion process or because of a relatively thin gas mantle (or because of gravitational contraction, 5-1). End February 2004]
[June 2004: Or by a very fast pulsar mechanism (5-1). Perhaps that the heavier a pulsating object is the more luminous and hotter it is as well as the faster it pulses with a pulsar mechanism (6-1).
Recently another bright X-ray source was discovered in the dwarf irregular galaxy Holmberg II. Big bang astronomers found that the mystery source sends out X-rays evenly in all directions at a tremendous rate, shining one million times brighter in X-rays than the Sun shines at all wavelengths of light combined¹⁷². I think that a big object with very heavy metals is the basic key to unravel the mystery of such objects rather than the “black hole” concept of big bang astronomers (see also 4-4). End June 2004]
[June 2004: Chandra X-ray observatory observations in 2001 indicate the presence of an unusually bright X-ray source in the star cluster MGG11 in the starburst galaxy M82¹²⁴. Big bang astronomers think that the properties of the X-ray source are best explained by a black hole with a mass of about a thousand times the mass of the Sun. When such objects are rather to be explained by so far unknown fusion processes, relatively thin gas mantles or by gravitational contraction then such objects (and bigger, producing hotter radiation like gamma rays) are likely much more to be found when huge numbers of objects are concentrated within a very small volume of space as suggested here, i.e. such hot objects then are likely to be found in the here mentioned “big balls” and therefore may explain the huge amounts of high temperature radiation in compact sources of AGNs. End June 2004]

[March 29 2005: There are so-called ultraluminous X-ray sources (ULXs) that radiate 10 to 1000 times more X-ray power than what big bang astronomers call neutron stars and stellar mass black holes. Some big bang astronomers believe these mysterious ULXs are more powerful because they are intermediate mass black holes. Other big bang astronomers think ULXs are regular stellar-mass black holes that appear to be much more powerful in X-rays because their radiation is beamed in a jet toward Earth³⁰⁴.
I think such objects descent from old (burned out) clusters of stars, like super star clusters (4-4), globular clusters or even dwarf ellipticals. Of course, I don't think those objects are “black holes” (5-1).
Big bang astronomers used Chandra to observe a ULX in the galaxy Messier 74 (M74), which is about 32 million light years from Earth. They found that this source exhibits strong, nearly periodic variations in its X-ray brightness every two hours³⁰⁴. This may hint towards a minor “big ball” (5-1), i.e. a minor compact source (this time not of an AGN). End March 29 2005]

A big ball, for instance with the size of our Solar System, filled with very many (slightly different) rotating/orbiting objects that may have their own peculiar velocities (4-1), may emit all kind of radiation in enormous amounts. This is my basic mechanism explaining the compact sources of AGNs. Of course, this “big ball” does not necessarily have to be extremely spherical.

AGNs show a high-energy cut-off at energies of around a few hundred keV⁴³ (conventional AGN models have problems explaining this high-energy cut-off⁴⁴). At energies higher than a few hundred keV, with a few notable exceptions such as NGC 4151, only blazar-type objects have been detected.
A few hundred keV corresponds with a thermal black body temperature of 10¹⁰-10¹¹ K. Higher temperatures than 10¹⁰-10¹¹ K may not be possible, at least not on the outside/surface of an object, for elements then may degrade. According to big bang cosmology⁸ protons and neutrons are constantly transformed into each other by interactions with neutrinos and electron-positron pairs above 10¹⁰ K. Thus 10¹⁰-10¹² K may be a critical temperature range explaining the high-energy cut-off of AGNs.
Inside a heavy object temperatures may be higher than 10¹² K (5-2).

There may be a difference between objects in an AGN “big ball”/compact source that have a gas mantle (perhaps in “big balls”/compact sources of all AGNs except BL Lacertae objects) and objects in an AGN “big ball”/compact source that don't have a gas mantle (perhaps in the “big balls”/compact sources of BL Lacertae objects, 5-3).
When a BLR prohibits hydrogen/gas to fall into the “big ball” (5-1) then this does not necessarily mean that the hydrogen/gas (that originally was) in the big ball (see also at Ionization cones, 5-1) has been processed into higher elements or has been thrown out by radiation pressure. Massive dark matter objects may have big gravitational pull on a relatively small layer of hydrogen/gas, thus radiation pressure by the glowing object may not be high enough to get rid of the hydrogen, while the pressure on the hydrogen by gravitational pull may not be high enough to produce nuclear fusion reactions. Thus most AGNs may have hydrogen/gas layers surrounding the objects in the compact source. (BL Lacertae objects may be an exception and therefore BL Lacertae object continuums may reach higher temperatures, 5-3.)
Though: in BLRs gas is pushed away from the compact source, but part of the BLR gas may fall into the compact source, which may mean that the objects in the compact source radiate (too) by nuclear fusion of gases (5-1).

The highest temperatures of AGNs are likely to be found at the very core of the central source of AGNs (i.e. the very core of the “big ball”) and from the very core to the more outer regions of the compact source/"big ball"/continuum source the temperature will go down. At a certain distance from the continuum source the starburst region may show up. The starburst region then may be the region where gas is not pushed away by radiation pressure of the continuum source anymore.

In the original galaxy or g-galaxy that originated the AGN there may have been many old galaxies/dark matter objects forming a rotating disk around the very (compact central) core of the galaxy/g-galaxy. When outboard gas from far away falls into the galaxy/g-galaxy much of the gas will be “caught” by the dark matter objects that form that disk. Thus a disk-shaped starburst region may be formed. An example of such a disk may be seen in the nearest active galaxy to Earth, Centaurus A; the disk was imaged by the Hubble Space Telescope in 1998⁴⁵.

[July 2003: If the nuclear bulge [July 2004: (or perhaps Sagittarius A*) End July 2004] of our Galaxy turns into the compact source of an AGN in the far future (5-1) then the spiral arms of our Galaxy may become a future disk-shaped starburst region when our Galaxy gets fuelled with hydrogen from intergalactic space. End July 2003]

Between the central source and the starburst region then may lie the Broad Line Region (5-1).

Unlike spectra of stars and galaxies, AGN spectra can not be described in terms of blackbody emission at a single temperature, or as a composite over a small range in temperature. Non-thermal processes, primarily synchrotron radiation, were thus invoked early to explain quasar spectra⁴³.
But the situation becomes different when one looks at AGN compact sources as big balls of rotating mass objects that have all kind of temperatures. Many different objects, with different temperatures over a broad range, may produce spectral energy distributions (SEDs) of AGNs that can be characterized crudely as a power-law.

A big ball of rotating (causing variability) hot “dark” matter objects (together with colder parts/objects in the central source) may account for long-term as well as short-term variability of the AGN (X-ray/UV/optical continuum) radiation (short-term variability may also be caused by supernovae as described in the starburst-AGN connection model).
When the radiation flux from hot heavy objects in the center of the AGN compact source is changed by objects further away from the center passing in front of them (or the center of the central source, which may be likely to have a higher rotation rate like the Sun rotates faster than the planets orbit, catching up) then the X-ray radiation continuum flux from the central core may change first, followed by UV and optical radiation coming from gas in BLR/starburst region.

There may be 4 types of mechanisms that cause variability:

1. rotation of the “big ball” causing long-term (irregular) variability
2. gravitational microlensing and/or obscuration causing medium-time variability
3. supernovae causing medium-time/short-time variability
4. pulsating qualities of heavy objects causing medium-time/short-time variability

Inside the very core of the big ball the biggest objects may be found that have the highest temperatures by gravitational contraction (or nuclear fusion within a thin layer). Further away smaller objects may cause lower frequency radiation. Variations may be caused either by rotation of the central source (thus bringing different objects to view) or by orbiting (and hence microlensing or/and view-blocking/obscuring) objects that lay more outward. One may think about variability as an inverse camera obscura effect. Instead of light going in (the camera obscura) light comes out because the hot inside emits hot radiation that can peak through the outside wall of colder objects, thus accounting for variability of the X-ray/UV/optical continuum.
[October 2003: (This may mean that the compact central sources of AGNs are much larger than expected so far: due to the time intervals of the light flux variations the compact central sources of AGNs are estimated to be one light day to one light week in diameter^43,75. The diameters may be much larger with an “inverse camera obscura mechanism” and/or mechanisms like obscuration or microlensing that may cause flux variations of the continuum.) End October 2003]
Such variations will be larger for massive hot objects laying more in the inner region of the central source, hence high-energy light will show stronger variability. Lower high-energy light is emitted by smaller and more numerous objects laying more outward, thus lower radiation will show less strong variability. But also: hot radiation may heat more outward laying material which emits the radiation later at a lower frequency, which too may account for larger variations at shorter wavelengths as well as why smaller-scale (few percent) variations that are seen in the UV on short time scales seem to be smoothed out at longer wavelengths.

One should keep in mind that the compact (central) source of an AGN may consist of a high number of old (merged?) galaxies/g-galaxies that still may have, in a way, their own peculiar orbiting/rotation velocities while orbiting the very core of the compact source (4-1), which may cause the variability's in fluxes to be non-periodic (perhaps over long times some periodicities may be found in some AGNs). And: if inside laying cores rotate in a different way (for instance: faster) than more outward laying cores then the variability in fluxes will be non-periodic (but perhaps not over very long times).

Variability by (more outwards laying) (concentrated groups of) objects may be caused by 2 mechanisms:
A. (old galaxies/g-galaxies/concentrated groups of) objects block radiation, thus decreasing radiation from the inner core
B. (old galaxies/g-galaxies/concentrated groups of) objects act as gravitational lenses, thus increasing radiation from the inner core

So far an important means of discriminating microlensing from intrinsic variability is that a microlensing event would have the same amplitude at all wavelengths (in general, intrinsic variations in AGNs are larger at higher frequencies)⁴³. This is not true if one takes a “cloud” of dark matter objects as the “object” that passes in front of the AGN. Multiple dark matter objects will cause larger intrinsic variations for light that comes from more inner parts of the AGN, i.e. light with higher frequencies.

If rapid variability in gravitationally lensed QSOs is attributed to microlensing by intervening objects in the foreground, then the surface-brightness distribution of the QSO continuum-emitting region must be very compact in order for the variations to be fast and of detectable amplitude⁴³. In the here described model AGNs can have extremely compact continuum-emitting regions.

Rapid X-ray variability may be explained by obscuration and microlensing, but perhaps also by: heavy compact objects may show pulsing qualities (5-2, 6-1, 6-2).

The variations in the X-ray continuum are apparently correlated with variations at UV/optical wavelengths. It is often suggested that the UV/optical spectrum is a reprocessed version of the X-ray spectrum. The above mentioned mechanism with gas in the BLR/starburst region (which lies days from the central source) reprocessing the X-rays from the central source may be the answer. The BLR region is (light)days away from the central source, which may explain why UV/optical variations often show up after a few days. UV/optical variations thus may show up with less strong/sharp variability than the originating X-ray variability.
In AGNs with no BLR the UV/optical variations thus may follow the X-ray variations sooner, i.e. (almost) simultaneous (because the gas is not pushed away from the compact/continuum source).

[January 2005: Miller and Homan, for the first time, found a connection between two characteristics of “black hole” observations: quasi-periodic oscillations (QPOs) and the broad iron K line. QPOs refer to the way the X-ray light seems to flicker. Using the Rossi Explorer, Miller and Homan studied a predominantly X-ray radiating object named GRS 1915+105, about 40,000 light years away in the constellation Aquila, the Eagle. They noticed that a low-frequency QPO of 1 to 2 hertz was tied to changes in the broad iron K line, as if the two features knew of each other. The fact that the two signals were in synch and were unaffected by other phenomena-such as “black hole” jet activity-strongly suggests that both are occurring very close to the “black hole”. And this, the big bang scientists say, rules out a theory stating that broad iron lines are created in “black hole” winds far from the object itself²⁷⁰.
Perhaps that the iron atoms are in a kind of Broad Line Region (5-1) surrounding the object and that the shape of the iron line is a function of the X-ray radiation/flickering of the object. The object may be likely to be a compact object, i.e. no “big ball”, with a pulsing quality. Though, perhaps that the X-ray flickering may be because multiple X-ray emitting objects spin around each other very quickly at a very short distance, or perhaps that one X-ray emitting object gets obscured or/and microlensed by orbiting objects that do not emit X-rays. End January 2005]

In the outer regions of the central source many small dark matter objects may have very low temperatures, which then may cause microwaves or even (short wave) radio waves coming from the outer regions of the central source. Of course, no temperatures below 2.73 can be expected to be found easily, which limits the range of possible radio radiation by thermal black body radiation. Though, perhaps lower temperatures than 2.73 are possible with a cooling down mechanism as described with pulsars in 6-1. Thus perhaps it remains to be seen if the radio spectra of compact AGN sources do not have a thermal origin, as is strongly believed by conventional astronomy. The lowest possible temperature may then cause the low-energy cut-off of radio waves from compact AGN sources. [July 2004: The Boomerang Nebula has a temperature of 1 Kelvin and is the only object found so far (July 2004) that has a temperature lower than the background radiation²¹⁵. So there is the possibility of objects with very low temperatures. In 6-1 it is suggested that the cause of the low temperature may be merging of dark matter objects (of two stars). The outer region of the compact source of an AGN may contain a lot of dark matter objects (and stars) which may get very low temperatures by merging of the dark matter objects (within the stars). End July 2004]
In our galactic nucleus Sgr A* is considered (by conventional astronomy) to be a nonthermal pointlike radio source, which thus may be doubted too.
[July 2003: Also: one may wonder whether sources like Sag A* and (thermal) (radio) sources in AGNs may have very strong gravitational redshift (5-4), which may cause radiation to be of (a little) lower temperature. End July 2003]
[May 2004: The in this chapter described mechanisms that can cause variability in what conventional science describes as “massive black holes” may also cause strong variability in Sgr A*¹¹⁹. End May 2004]
[June 2004: Sgr A* can be seen as an old AGN at the center of an old spiral galaxy Sgr A West (4-1). Fast X-ray variability (4-1) can be explained by a hot objects in the inner core of Sgr A*. The (X-ray) light coming from the inner core then would peep out every now and then through “holes” within the surrounding wall of less hot objects (5-1) and fast (though less fast than the X-ray variability) infrared variability¹²⁵ then may come from objects (and/or dust) further away from the core of Sgr A*. Infrared temperature objects(/dust) may be surrounded by a less thick wall of lower temperature objects/dust (producing radio radiation). End June 2004]

With the here described model of AGN-nuclei being formed by enormous balls, i.e. compact sources, and disks, i.e. starburst regions, of old (“dark”) matter (plus attracted starburst-hydrogen) it is not surprising that AGNs show such enormous radiation fluxes and that their surface brightness is very high (especially the surface brightness of the compact source).

Those enormous balls/disks can originate from: a galaxy that has shrunk, a cluster of galaxies that has shrunken, but also a supercluster or even a supersupercluster that has shrunken (for compact sources to originate: shrinking and merging).
[September 3 2007: If AGNs descend from shrunken galaxies or shrunken clusters of galaxies which are extremely old, then one can imagine that there may be AGNs that have much old blackened stars and remnants of old blackened stars (with much dust and rocks) surrounding them. In fact there may be so much dark obscuring material in the from of dust, rocks, planets, dark stars, etc. that the AGN may be obscured by it. Recently such AGNs have been found. An international team of astronomers using NASA's Swift satellite and the Japanese/U.S. Suzaku X-ray observatory has discovered a new class of AGN. The AGNs are so heavily shrouded in obscuring material (which may be gas, dust, rocks, planets, old darkened stars, etc.) that virtually no light gets out of the AGN. The AGNs were found by looking for high-energy X-rays which can punch through thick gas and dust. The team thinks these newly discovered AGNs are completely surrounded by a shell of obscuring material. Their results imply that there must be a large number of yet unrecognized obscured AGNs in the local universe. In fact, these objects might comprise about 20 percent of point sources comprising the X-ray background, a glow of X-ray radiation that pervades our Universe. NASA's Chandra X-ray Observatory has found that this background is actually produced by huge numbers of AGNs, but Chandra was unable to identify the nature of all the sources⁴⁶³. End September 3 2007]
All kind of old dark matter clustering magnitudes, i.e. galaxies/g-galaxies, can bring AGNs in all kind of magnitudes. Thus one can imagine that quasars for instance can be found at very high redshifts and that a quasar at z=5 can have an enormous output of radiation. [July 2003: I think a little different about this now, because I have realized that the redshift of quasars may also be due to gravitational redshift (5-4) next to tired light redshift. End July 2003]
[May 2004: Though, I rather see quasars as extremely far away because of tired light redshift than as near because of gravitational redshift, 5-4. Also: perhaps that the nuclear bulge or even part of a nuclear bulge of a galaxy like our Milky Way can turn into the compact source of an AGN. End May 2004]

And: with the tired light hypothesis instead of expansion redshift (1-2) quasars are even much further away than expected so far (no more relativistic z-distance calculation, 5-3). Thus quasars with high redshifts may be even much more luminous than expected so far.
This may explain why quasars are rare at higher redshifts (i.e. higher than z=3.5). A very luminous quasar may (have to) originate from a large “object” like a supercluster or even a supersupercluster. A (super)supercluster shrinking to a universal engine would not be likely to occur often. Though perhaps we may see a lot of them the day telescopes pierce dramatically deeper into space.

(With tired light redshift it may be so that light redshifts more when going through space with relative more mass in it, like our Local Supercluster region. Thus light that goes mostly through large empty nonluminous voids may redshift less, compared to light coming from an object in our Local Supercluster. If so then this would mean that quasars with high redshift values may be at even further distances with even bigger fluxes.) [July 2004: This effect may have been measured: light going through rich galaxy clusters redshifts stronger (1-2). End July 2004]

It is observed that increasing luminosity of quasars corresponds to increasing metallicity in the emission line region. In the here described model increasing luminosity comes with larger amounts of dark matter (with heavy elements) which then may account for increasing metallicity (many dark matter objects will often clash, thus producing much dust/higher metallicity; but also: dark matter objects may produce supernova Type Ia, 5-2). [July 2003: In the case the high redshift of a quasar is caused by the quasar being far away then the quasar has a high luminosity which means that a lot of dark matter should be in the quasar or else the quasar would not have been high luminous. (The “big ball” or compact source is very luminous because of a lot of objects in a very small volume and hence in this small volume a lot of dark matter objects clash, thus causing much dust/high metallicity.) In the case the redshift of the quasar basically is caused by gravitational redshift then the quasar is very compact and probably has much dark matter relative to hydrogen. End July 2003]

[November 6 2007: Big bang astronomers have found that the gas in the center of the compact sources of quasars consists of almost pure hydrogen and helium, whereas the stars and other material in the surrounding giant galaxies are heavily contaminated by other elements such as carbon and oxygen. The astronomers think that the gas spirals towards a black hole⁴⁶⁹.
The old dark objects in the old formerly compact source may have bound heavier elements than helium by gravity over a very long time, which may explain why so little heavier elements than helium are found in compact sources of quasars. When gas falls into the compact source containing much elements heavier than helium then those metals may sink down in the stars to the heavy nucleus of the former dark matter object (7-1). The astronomers may have observed outward layers of gas of star surfaces in the compact sources of quasars instead of gas spiraling towards a black hole. End November 6 2007]

In general brighter AGNs are found in more luminous galaxies⁴³. With AGNs being universal engines that attract hydrogen, thus originating a host galaxy, this is not surprising.

When will an old g-galaxy or young universal engine start with AGN activity?
Perhaps a g-galaxy is a very stable system that can be around for a very long time and which may be very hard to observe if it is old cold dark matter.
But when hydrogen (and perhaps also dust and dark matter objects) is attracted from very large distances and the attracted matter finally concentrates in and around the g-galaxy and falls (in)to the (old) g-galaxy nucleus then the g-galaxy (especially the nucleus) may shrink, thus turning itself into a (young) universal engine. This way a very concentrated (inner)sphere of the old dark matter g-galaxy may become a rotating ball of matter producing AGN features. (Right now the origin of the gas that fuels the central engine of an AGN and the mechanism that brings the gas to the very central region are still controversial.)

But, perhaps a g-galaxy don't need any infalling matter to turn itself into a universal engine with AGN features, or perhaps a universal engine only needs a certain minimum amount of attracted matter falling in, after which it produces AGN activity. Thus it may be that AGNs can be embedded in host galaxies that are very small and that quasars may have no host galaxy at all, which may have been observed²⁹: “naked” quasars.
But also (what is often suggested): the bigger an AGN (i.e. more luminous) the more “the big ball”/starburst region outshines the host galaxy of the AGN, and thus the more the AGN appears to be “naked”.
[June 2004: Right now I give it most chance that there are no “naked” quasars. Quasars that appear to have no host galaxy are just much further away than expected so far by big bang astronomers (4-4). End June 2004]

(Seyferts, radio galaxies and quasars may represent different phases of AGNs. The different phases may be the reason why certain types of host galaxies link with certain types of AGNs. See 5-3.)

It is found that ~ 15% of Seyfert galaxies have companions, whereas only ~ 3% of a control sample of normal galaxies have such companions⁴³.
AGNs are older objects than galaxies and thus it may not be surprising that AGNs are more likely (i.e. 5 times more) than normal galaxies to have a similar companion object (in 4-3 it is explained that: the older the objects the stronger the tendency that they are found in binary systems).

Companions of Seyfert galaxies are also likely, relative to companions of normal galaxies, to show strong emission lines in their spectra⁴³. This may be easily explained if Seyferts are likely to originate from shrunk galaxies or shrunk clusters of galaxies, which then will be in similar stages of their evolution if you take the galaxy formation explained in 4-1 in mind, see 5-4.

In our Sun's chromosphere exactly the same mechanism is at work (where the Sun's corona, with its forbidden lines, shows more Narrow-Line Region characteristics).
And: several authors⁴⁶ have pointed out that the photoionized extended envelopes of stars such as red giants and supergiants have physical characteristics remarkably similar to those of the BLR. This may be everything but a coincidence. Especially when one takes in mind that red giants and supergiants may be, as suggested in 6-2, very big heavy element cores surrounded with (large) gas mantles. The here proposed AGN model is the same: a “big ball” (with many heavy element cores) surrounded by a gas mantle, i.e. BLR. (Perhaps it remains to be seen how much or whether there is gas inside the “big ball”, i.e. whether or not the BLR is only the outward part of a large gas sphere as the chromosphere is in our Sun or as in red giants or supergiants.)

[March 28 2005: One may argue that if the BLR is a gas mantle surrounding the compact source of AGNs then we would not see the compact source, instead we would see the gas mantle, like we see the Sun's chromosphere and not what is underneath the Sun's chromosphere. However, when one thinks of the gravitational forces and radiation pressure of our Sun and the gravitational forces and radiation pressure of red giants one understands that in the case of red giants the “gas mantle” is not as massive as the Sun's chromosphere. The gas of the BLR may be much more dilute/less massive than the “gas mantle” of a red giant because of much stronger gravitational forces combined with much stronger radiation pressure by the compact source of the AGN. Therefore at least part of the radiation coming from the compact source may find its way through the BLR. End March 28 2005]

[June 2004: One out of million stars in our Galaxy is a supergiant, like Betelgeuse, which even at a distance of 425 light-years is the seventh brightest star visible in the northern hemisphere. The photospheric surface of Betelgeuse is about as large as Jupiter's orbit. So far telescopes on Earth detected the warm gas in Betelgeuse's weak chromosphere up to only about five times the radius of the photosphere.
New observations with the Space Telescope Imaging Spectrograph, Hubble's high-precision and ultra-sensitive spectrometer, show that the warm chromosphere of Betelgeuse extends out to more than fifty times its radius in visible light (i.e. the radius of its photosphere; the weak chromosphere of the Sun extends only a few percent of the radius of the photosphere). The chromosphere of Betelgeuse is very turbulent. New observations show that the bubbling action of the chromosphere tosses gas out one side of the star, while it falls inward at the other side. Parts of the star's unstable surface sometimes vigorously bulge out in different directions, piercing long warm plumes into the cold dust envelope. At large distances from the surface, the density of the cold atmosphere strongly decreases¹⁵¹.
This description of the chromosphere of Betelgeuse comes close to the description of the BLRs in AGNs, which too have gas in a very turbulent state, which originates emission lines with extreme widths in BLRs. A chromosphere extending more than fifty times the distance between the Sun and Jupiter means that photons going from the photosphere towards the outer parts of Betelgeuse's chromosphere need more than a day travel time. A chromosphere that big comes close to the magnitudes of BLRs in (small) AGNs.
One then wonders if there can be very big stars and very small AGNs that resemble each other, i.e. very big stars may have multiple dark matter objects (surrounded by gas) inside that revolve around each other (the whole radius of visible light, i.e. the photosphere, surrounded by the chromosphere) where as small AGNs may have multiple dark matter objects (which may be surrounded by gas) inside that revolve around each other (the whole compact source surrounded by the BLR).
Perhaps that a supergiant star can be a star with (many) multiple objects (small stars) inside that have gas fusion going on in their layers. A supergiant star thus may originate from a concentration of many dark matter objects that have been fuelled by gas.
The dust envelope surrounding Betelgeuse too is something that bears similarity to AGNs, which also have a disk of dust (5-1).

When a supergiant can be an object that consists of multiple stars then one may expect that some very large stars show variability because the multiple objects within the stars orbit each other, thus bringing different magnitudes of luminosity.
One longstanding problem with gauging the brightness of stars at great distances is that what seems at first to be one amazingly bright star turns out on closer examination to be a cluster of nearby stars. LBV 1806-20 is a star that could be as much as 40 million times the sun's brightness, big bang astronomers think that it may be the most massive and most luminous star ever discovered (i.e. in January 2004). Astronomers have known about LBV 1806-20 since the 1990s. At that time, it was identified as a “luminous blue variable star”, a relatively rare massive star. Such stars get their names from their propensity to display light and color variability in the infrared spectrum. Luminous blue variable stars are extremely large, with LBV 1806-20 probably at least 150 times larger than the sun. More study will be needed to determine the distance and singularity of LBV 1806-20 in order to establish whether the object is truly the most massive star known or that it is a collection of stars in a tight orbit around each other¹⁵². End June 2004]

[March 25 2005: A team of big bang astronomers has checked out the X-ray sources of many far away objects, i.e. the centers of far away galaxies. The team has observed that the chemical abundance of iron in the centers/AGNs of very far away galaxies is about three times higher than in our Solar system. This came as a surprise for them, for they had not expected to find so much iron in their early big bang universe. The width of the iron line indicated that the iron atoms must have high speeds²⁹⁹.
The far away galaxies were probably further away than the astronomers thought (5-3). Being spotted at a very big distance the AGNs in the centers of the galaxies ought to be strong/big/massive AGNs. In strong/big/massive AGNs a lot of iron can be expected. The Broad Line Region of strong/big/massive AGNs will show strong widths. End March 25 2005]

[May 2004: The center of the active Circinus spiral galaxy spews out gas and dust in a broad spray like clouds of vapor from a steam locomotive⁸⁹. While other active galaxies drive narrow relativistic jets, the Circinus center drives a comparatively meek wind. It is not understood by big bang astronomers what mechanism causes the meek wind⁸⁹. Perhaps that radiation pressure by continuum emission from a “big ball” can explain the wind. End May 2004]

Cross-correlation lags of helium are shorter than the cross-correlation lags of hydrogen. In general: the cross-correlation lags of heavier elements are shorter than those of lighter elements⁴³. This may be because heavier elements will be stopped later by radiation pressure from the AGN central source than lighter elements.
Also: HeII has a shorter cross-correlation lag than HeI⁴³, which may be because HeII, having an electron less, is more compact than HeI (and thus HeII will be stopped later by radiation pressure).

One may expect this “compactness thing” to be kind of the same for gravity particles (causing gravitational forces) relative to photons (causing radiation pressure), but this may not be the case at all. Gravity particles are likely to be much smaller and to be around in far greater numbers than photons. Thus the “compactness thing”, i.e. the density, of an atom will have much stronger influence on the “hit chance” by photons than the “hit chance” by gravity particles (3-2). Thus more compact, denser atoms (i.e. HeII relative to HeI) may come closer to the central source before stopped by radiation pressure than less dense atoms.

Equivalent widths of the CIV emission line tends to decrease systematically with increasing continuum luminosity: the Baldwin effect. The origin of the Baldwin effect is not understood⁴³.
If the luminosity of a certain compact source increases then the BLR is pushed further away from the compact source. The BLR shell becomes thinner and the velocities of the CIV decrease, thus the widths of the CIV emission line decrease.

In a single spectrum different emission lines may have different widths. It is often found, for example, that the helium lines HeIIλ4686 and HeIλ5876 are broader than the hydrogen Balmer lines in BLRs⁴³. This too may be due to helium coming closer to the AGN core and thus helium deals with more fierceful (radiation pressure/gravitational) forces and hence gets higher velocities, i.e. broader emission lines.

Also: the higher-ionization lines (e.g., HeIIλ4686) are shifted blueward relative to the lower-ionization lines (e.g., HeIλ5876)⁴³. This may be due to HeI being stripped of an electron near the compact source, then moving away (by radiation pressure) from the compact source as HeII (which then is blueshifted relative to HeI). The HeII is stopped by gravitational attraction and changes to a HeI by gaining an electron and goes back to the central source (hence HeI being redshifted relative to HeII). (Closer to the central source the helium gets hit more by photons and thus closer to the central source helium is more likely to become HeII.)

Changes in emission-line profiles are not reverberation effects, and they are not correlated with the continuum variability in any obvious way⁴³. Line-profile changes may be due to atoms, or perhaps rather clouds of atoms (with different concentrations), moving to the compact source and/or away from the compact source while the compact source and BLR are rotating (with different ways of rotation, so no correlation with the continuum variability). Rotation that may bring different atoms (clouds of atoms) in the line-of-sight and hence emission-line profiles change.

Above I described in A big ball that the massive objects in the compact source may glow by gravitational contraction. But perhaps that those objects produce their hot radiation (too) by nuclear fusion processes. In 6-2 it is described that white dwarfs may be massive dark matter objects with relatively little gas that is fused into higher elements as in stars. But because the gas layer then is relatively small the stars/white dwarfs may be much hotter than normal stars. Thus perhaps that the compact sources of AGNs are big balls with many (big) white dwarfs, or: stars with big cores of heavy elements, that fuse gas into higher elements.
Remains the problem: How are the compact sources of AGNs fed with gas if a BLR pushes the gas away?
Part of the gas of the BLR may fall into the compact source. For instance: gas may be channeled from the BLR to the compact source the moment a more outward object or compact group of objects (which are colder, thus producing less radiation pressure) in the compact source blocks radiation coming from the more inner parts of the compact source. Then gas may have its chance to fall into the compact source. Thus the compact source may be fed with gas.
I like this fed-by-gas compact source model most. Also because there is not much difference between the continuums of Seyfert 2s (that have no BLR, so gas falls into the compact source) and Seyfert 1s. Though, nuclear fusion and “glowing” by gravitational contraction may be at work together.

[June 2004: A few years ago astronomers reported to have found the first very distant representative of a Type II QSO at a distance of z=3.7¹⁸⁰ and recently more Type II QSOs were reported to be found at large distances (z > 3)¹⁸¹.
Every now and then there may be a QSO that has a compact source strong enough (i.e. enough hard X-ray radiation) to bring the AGN in the QSO class (instead of the Seyfert class) while at the same time the compact source of the QSO is not dense/compact enough (yet) to bring radiation pressure (dense enough) to originate a BLR. Such very far away Type II QSOs may then be found when very large concentrations of matter (i.e. for instance in the centers of superclusters) have such characteristics, i.e. a strong radiating compact source not strong enough yet to produce a BLR. (Such sources may not be found relatively nearby when the nearby environment of our Galaxy is in a certain “chappell state”, 5-4.) So a QSO may be fuelled by gas, enough to be a Type II QSO, but not enough (yet) to have a BLR established itself.
Another, perhaps much better, explanation may be: such sources are no Type II QSOs, but clusters of Seyfert 2s that are mistaken for one (Type II) QSO. At a redshift of over z=3 I think that big bang astronomers mistake clusters of galaxies for galaxies because the distance to objects at z=3 are much higher with tired light redshift (of an infinite universe) than with expansion redshift (of a big bang universe, 4-4). Therefore it may be no surprise that big bang astronomers claim to have found Type II QSOs at distances over z=3, for what they really may have been observing could be multiple Seyfert 2s.
This may mean that also Type I QSOs very far away (often) rather may be clusters of Type I QSOs than single Type I QSOs. Very far away QSOs being clusters of QSOs (within clusters of galaxies, with QSOs outshining their host galaxies, 4-4) rather than single QSOs would solve two complications concerning far away QSOs. One is that very far way QSOs would be extremely big when being at very large distances, perhaps to big to be true.
The space density of very high-redshift (z larger than 3.5) QSOs is thought to be extremely low (5-3), which may be explained by clusters of QSOs instead of single QSOs.
The other problem that may be solved is that radio-loud AGNs constitute a small minority of the AGN population, except at the very high-luminosity end of the distribution, where as many as 50% or so of AGNs are radio-loud quasars⁴³. When the high-luminosity end of the distribution often concerns high redshift quasars then clusters of QSOs instead of single QSOs may explain part of the difference, 5-3.
Approximately 50% of the host galaxies of QSOs show morphological peculiarities (5-3), which may (partly) be explained by clusters of galaxies instead of galaxies at high redshifts. End June 2004]

When Seyferts have compact source regions that are less hot then those colder regions produce less radiation and hence cause less radiation pressure that causes broad emission lines. Thus a rotating compact source, i.e. “big ball” may explain Seyfert 1.5s turning into Seyfert 2s and back again within years.
Thus the above described rotation of the big ball (5-1) that may cause long-term variability in the central source may cause transformations of Seyfert 1.5s and 2s too.
This view may be supported by observations of a few highly variable Seyfert 1 galaxies which have become very faint, with the broad components of the emission lines practically disappeared⁴³.
Additional support may be found in the fact that Seyfert 2 galaxies have significantly lower hard X-ray luminosities than Seyfert 1 galaxies⁴³, thus Seyfert 2s probably have less strong continuum/radiation pressure.
And: high-ionization narrow lines tend to be found only in Seyfert 1 spectra⁴³, which also indicates that the continuum/radiation pressure of Seyfert 1s are stronger.

(As mentioned (5-1): continuum variability may show no periodicity because different regions in “the big ball” may have peculiar velocities. Thus variability between Seyfert 1.5s and Seyfert 2s may show no periodicity either.)

Seyfert 2s may evolve into Seyfert 1s (for good, I'm not mentioning Seyfert 1/2 variability here) by shrinking of the compact source, which then produces stronger radiation pressure/gets a higher surface brightness, until a BLR originates.
(Seyfert 1s may evolve into radio quiet QSOs or radio loud galaxies, 5-3.)
[February 2004: Perhaps Seyfert 2s too evolve into Seyfert 1s when more gas has flowed into the compact source and thus more gas is fused, causing stronger radiation pressure (5-1). End February 2004]

Bigger Seyfert 2s (more luminous than Seyfert 1s) have more continuum. This continuum then ought to come from a “big ball” that is more luminous (with more luminous objects in a larger compact source), but which still has a surface brightness/radiation pressure that is too low to create a Broad Line Region.

The narrow-line to broad-line luminosity ratio is a decreasing function of radio luminosity: the narrow lines are relatively weaker in more luminous radio sources⁴³.
This may be explained by: more luminous radio sources may have stronger continuum/radiation pressure which may account for relatively stronger concentrated gas in BLRs (leaving less radiation for NLRs).

Seyfert 2 galaxies are less (or not at all) polarized compared to Seyfert 1 galaxies, the continua of Seyfert 2 galaxies are in general not polarized⁴³.
A polarized spectrum can result from scattering or reflection of the AGN continuum, either by dust or by free electrons⁴³.

Seyfert 1s may have attracted more (outboard) dust, or produced more (inboard) dust (by clashing dark matter objects and/or supernovae), which may cause polarization (5-3). [July 2004: This can be seen as support for Seyfert 2s shrinking into Seyfert 1s, thus having more dark matter objects in a smaller volume of space, resulting in more clashes between dark matter objects producing dust. Shrinking also means more concentration of dust. Also, when Seyfert 2s are progenitors of Seyfert 1s, then there has been more time for dark matter objects to clash as well as more time for supernovae to produce dust. End July 2004]

Polarization by electrons may be most likely. The polarization of the featureless continuum of the Seyfert 2 galaxy NGC 1068 (which is an exception to the Seyfert-2-no-polarization rule) is wavelength independent as far into the UV as 1500 angstrom, which indicates that the scattering particles are electrons rather than dust⁴³. And: the observed polarization in the continuum of AGNs increases dramatically towards shorter wavelengths⁴³.
With the here described BLR mechanism ions are pushed away by radiation pressure, but the electrons of the ions may fall into the compact source of the AGN causing more polarization closer to the center. Thus one may expect polarization to increase towards shorter wavelengths. Seyfert 1s have BLRs and thus electrons may fall inward, causing polarization (5-3).

Seyfert 2 galaxies sometimes show an extended component of continuum emission whose origin is unknown⁴³.
A shrunk g-galaxy or universal engine can have all kind of assemblages of dark matter objects and thus can have all kind of extended parts (i.e. old shrunk galaxies that only later fuse with the center of the compact sources), which thus may easily explain the extended component of continuum emission of some Seyfert 2 galaxies.
Also: if Seyfert 2s are relatively young AGNs then it is logic that some Seyfert 2s do not have a spherical “big ball” (/disk) yet (the AGN compact source is “under construction”).

There is X-ray (“continuum”) emission coming from the center of our Galaxy. The X-ray emission map shows very many discrete sources (which then may be gravitationally glowing “dark” matter objects or, rather, “dark” matter objects/white dwarfs fed by infalling gas). The overall picture is that of an oval heap of X-ray sources, with the major axis in the galactic equator, and with several extended parts⁸.
If both the galactic center and Seyferts are universal engines than the explanation of the extended X-ray/continuum sources of both may be found in the same direction: old more outward laying shrunk galaxies (of the old g-galaxy) that only later become “one” with the central source.

In the NLR region a similar process may exist as in the BLR: clouds may get pushed outwards (a little) by radiation pressure and pushed inwards (a little) by gravity. “A little” and hence narrow lines instead of broad lines.
Other factors may play a role. Like stars. Stars because unlike the BLR where the line widths appear to reflect the potential of the central source, the NLR widths reflect the gravitational field of the stars⁴³. (Though, observations indicate that the NLR gas is photoionized by the AGN spectrum, and not by stars in the nuclear regions⁴³.)
Perhaps that in the NLR atoms are more in the form of clouds where in the BLR they are more individual atoms/ions, or perhaps rather: streams of atoms/ions. The permitted lines in a Seyfert 2 have about the same widths as the forbidden lines⁸. This may mean that the NLR gas concentration is different in different parts of the NLR region that have the same radial distance to the central source; this may favor the suggestion that NLR atoms are more in the form of clouds.

There have been measurements that show continuity between the NLR and the BLR. In both BLR and NLR there is stratification of some sort, with either density or ionization level (or both) increasing towards the center⁴³. If the density and velocity dispersion increase as one gets closer to the nucleus, the NLR may merge more or less naturally with the BLR⁴³.
Then it is just that somewhere dust ought to start being around (because the region becomes less cold, so no sublimation of dust anymore) and somewhere dilution allows forbidden lines to appear.

With the above BLR model the merging of BLR and NLR may make sense, because some individual atoms/ions in the BLR will get faster velocities (by being hit, by chance, by more photons) and thus those ions are likely to go to the NLR, and: there may be no reason why there wouldn't be atoms/ions falling into the BLR.

Seyfert 2s don't have a Broad Line Region, so gas that falls into the very core isn't pushed outwards. Thus, in the case of Seyfert 2s big amounts of gas may fall on the central AGN core of a Seyfert 2 and the same process may start as in collapsing red giants or in YSOs: gas is squeezed out (bipolar) along the rotation axis. Thus ionization cones may be produced.
Ionization cones have been detected in somewhat more than a dozen AGNs, primarily Seyfert 2s⁴³.

Gas falling into a Seyfert 2 core may light up on dark matter objects and thus finally cause stronger radiation pressure coming from the AGN core, thus creating a BLR and thus changing a Seyfert 2 into a Seyfert 1.
Also: more gas in the core will cause stronger inertial forces and so the compact source will shrink faster and dark matter objects will merge faster into more massive objects that will have higher temperatures, thus (too) raising the surface brightness of the compact source as well as the radiation pressure.
Thus Seyfert 2s may be progenitors of Seyferts 1s (LINERs may be progenitors of Seyfert 2s, 5-3).

Part of the gas falling into the compact source (or perhaps rather: the center that may be on its way to become a compact source) of a Seyfert 2 may not flow out of the compact source (into the ionization cones) and stay in the compact source. Thus the objects of compact sources in Seyferts (and AGNs in general; though BL Lacertae objects may be an exception, 5-3) may be surrounded with layers of gas (5-1).

Seyfert 1s may become radio quiet QSOs (5-3). Perhaps the outflowing gas, i.e. the ionization cones, of Seyfert 2s (on their way to become Seyfert 1s) later can become broad absorption line (BAL) systems (5-3).

It may be very likely that a lot of new material (stars, gas, dust, dark matter objects) has fallen into the nucleus of our Galaxy, i.e. the old g-galaxy. Thus the shrunk g-galaxy in the nucleus has become more compact: by shrinking and by additional matter falling into the nucleus of our Galaxy. Thus it may be that older galaxies like spirals and irregulars Is have nuclei that are hold together stronger than nuclei in younger galaxies like ellipticals (which are host galaxies of quasars).
Also: in younger galaxies there may be more “pull” by outward laying material where in older galaxies there may be more “pull” by inward laying material (that has fallen into the nucleus).
Thus one may expect blobs of material escaping from ellipticals/younger galaxies rather than from spirals/older galaxies.

Also the radio galaxy M87 shows knots of material leaving the galaxy. An explanation may be that the knots of material have left M87 because of radio loud activity, i.e. streams of radio loud material flowing from the nucleus may have taken knots of material with them on the way out.
And: radio loud activity reduces the mass in the compact source of an AGN (5-2) and thus gravitational grip by the compact source becomes lower.
[February 2004: After a period of radio loud activity a quasar/QSO or radio galaxy may have lost a lot of mass in its very center and thus blobs of material that were orbiting the center won't be attracted so strong anymore by the center and therefore may leave the AGN. End February 2004]

Perhaps that the torus can be originated from old outward orbiting material of the old g-galaxy (that originated the AGN) only (or as good as only). Such outward orbiting material, i.e. old galaxies or old (smaller/minor) g-galaxies, once far away from the (old) center of the (major) g-galaxy (which has become the central region, i.e. compact source and starburst region, of the AGN), may have assembled themselves in a disk, which then may consist of many (relatively small) dark matter objects that may have crashed a lot and thus may have caused a lot of dust. One may call such torus material inboard material.

[June 2004: Not only AGNs have gas/dust tori. Also galaxies have gas/dust tori, or rather: gas/dust disks (on the inside, 4-3, as well as on the outside, 4-4), which I also explain with dark matter objects within old galaxies/g-galaxies clashing. Also stars have gas/dust tori in a way: accretion disks, which I also explain with dark matter objects/debris that may have come to fly around the stars, 7-2.
The galactic center is embedded in dust⁸, which then can be explained for the same reasons, i.e. 4-3 or when it turns out that Sagittarius A* is an old AGN (both reasons are almost the same since (big) old shrunken galaxies as well as AGNs become/are the centers of galaxies attracting new matter from intergalactic space). Also the gas/dust disk surrounding the galactic centers of other galaxies (the centers are often referred to as black holes by big bang astronomers), for instance the disk of dust and gas surrounding the center of the Circinus galaxy⁸⁹, can be explained by the same principle of old galaxies/g-galaxies orbiting the centers, thus producing dust by clashing dark matter objects.
I like this, i.e. to have all this gas/dust stuff of different celestial objects explained by the same principle. End June 2004]

Probably most, if not (about) all, gas is outboard gas, where dust may be outboard as well as inboard, and most, if not (about) all, dark matter (objects) may be inboard.

(Inside (in the center of) this torus another disk has formed itself from much more concentrated dark matter objects and concentrated gas: the starburst region. Inside (in the center of) this starburst region lies the central compact source, which consists of even much more concentrated matter.)

In chapter 3-2 and 4-3 it is explained (with pushing gravity) that one may have to differentiate for different materials, different outboard matter (gas, dust and dark matter objects), coming from intergalactic space. Gas may fall “easier” straight to an object in space than dust, while dust may fall “easier” to an object than dark matter objects: dark matter objects will stick more strongly to the direction of their incoming speed, i.e. dark matter objects start orbiting a rotating (rotation that will influence the direction of the dark matter objects) central region with a universal engine/compact source inside (thus the dark matter objects form a disk, like planets in solar systems, 7-1) where dust falls stronger into the central region and gas clouds probably fall even more stronger into the central region. But by doing so dust and gas may “stick” to the dark matter objects that orbit the central region.

The torus and the starburst disk of an AGN may form some kind of gravitational shield (3-2) to the central source. Thus the BLR clouds may be pushed by radiation pressure into the starburst region (more easily than the BLR clouds are pushed into the NLR (not shielded by torus/starburst disk). Thus perhaps that gas/atoms/clouds from the NLR can go to the BLR and then, finally, get pushed into the starburst region (perhaps it remains to be seen whether or not there is also a BLR between the compact source and the disk (i.e. in the plane of the disk)).

Narrow-line X-ray galaxies (NLXGs) are Seyferts whose optical spectra are heavily reddened and extinguished by dust within the galaxy. NLXGs may be (older) Seyferts that have attracted more outboard dust, or they may have, for some reason, more (inboard or outboard) dark matter objects that have clashed a lot (for example because galaxies or g-galaxies started orbiting the central region with opposite orbiting directions, thus clashing a lot and hence forming much dust, 7-2).
The dust in/around ultraluminous far-infrared (FIR) galaxies may be the result of frequently clashing dark matter objects because of opposite orbiting velocities of galaxies or (minor) g-galaxies. The dust may also be outboard dust. Radio loudness perhaps may be produced by cold dust (though not likely, 5-2) that is poured out by an AGN. This dust may originate FIR galaxies too.
(Of course, dust produced by supernovae will play some part too.)