The Sun

I don't quite see why the velocity of the black hole through the gas and dust should reduce the amount of its emissions. Wouldn't a black hole in motion encounter more gas and dust than a stationary one? The emissions from the black hole would be from the black holes 'rest frame', so why would the black hole's motion through the universe have any large effects on the jets? Here is an article about an suspected black hole or quasar moving rapidly through space, possibly ejected from merging galaxies:

http://www.world-science.net/exclusives/051111_holefrm.htm

 

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Again i ask you to read points (2) & (3) of my post two prior now as this is clearly explained there, but briefly if it goes very fast the collisional heating that causes the gas infalling to make a quasar will not occur. The mass in the path of the event horizon diameter circle of the black hole would just disappear as the black hole "cores" out hollow cylinder thru the cloud and gives a gravitational impulse towards the center of the empty cylinder to all the gas that did not get "eaten." Without any increase in the collision among the atoms beoing eaten there would be no increase in their radiation. Any radiation the black hole does induce in this uneaten gas occurs when their kinetic energy gain by the gravitaional impulse causes them to collide in a line source on the axis of the initially empty cylinder. Understand now? If not I give up - Read points (2) and (3) until you do.

 

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Billy T, perhaps you should read how a rotating black hole accrets matter. The matter does not fall down the 'throat' of the hole, but enters the accreation disk from the 'side' of the event horizon. Real black holes rotate at tremendous velocities, spinning any incoming gas or dust along with the accretion disk. The central, or 'throat' portion of the black hole ejects matter away from the hole, due to the jets. This is based on actual observation with different types of telescopes (radio, x-ray, etc.), not the physical theory describing the old, non-rotating black hole scenario. If you do not understand the difference, I give up! (no offense

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I do not know much about Kerr holes, which is what the rotating BH is called and I am sure you do not either. It was something like 20 years after the simpler non rotating BH equations were solved before the experts in this field were able to solve the equations, (Kerr finally found a solution first. I don't even know it Kerr's solution is the only one, but I think it is still the only one known. Itried to read his paper years ago.) Some of what you say is true, but the in-falling plasma from a near by star that makes the quasar rotates in the accretion disk to conserve its angular momentum. Its accretion disk is always in he plain of the source star and the black hole regardless of orientation of the axis of the jet, which I think is more related to the angular momentum vector of the Kerr BH.

All your infro continues to be based on popularized astronomical observation and simplified reports. I am quite sure you can not do the math, nor can I, to really understand. None of your post applies to a small (few solar masses) BH travel fast thru cosmic gas cloud, far from any star.

I do know a little, perhaps more than you, about BH near a star. I.e. a quasar, but again for the third (and final time) time all that is irrelivant to the dark visitor traveling fast far from any star. You might as well drag out whatever you may know about the sequence of stellar fusion cycles as that would be equally relivant (i.e. also irrelivant).

 

Billy T, you seem to think only black holes feeding off a companion star, such as most quasars, have jets. Not true. All black holes, whether we can see anything they are feeding off of, or not, emitt the jets. No, I can't do the math, but said you could not either for Kerr black holes. Even stellar-mass (formed from 10 solar mass or above stars) have these jets, and, yes, they are all Kerr black holes. All stars that have ever been observed have been rotating, all black holes formed from rotating stars will be rotating black holes. If you don't understand the math, why do you want me to link to math intensive papers? The Schwarzschild maths are not sufficient to understand true black holes. Another excerpt? Why not.
"Reissner-Nordstrøm Black Holes

A step up is the Reissner-Nordstrøm black hole. It has the singularity and two event horizons. The outer event horizon is a boundary where time and space flip. This means that the singularity is no longer a point in space, but one in time. The inner event horizon flips space-time back to normal.

Kerr Black Holes

A Kerr black hole adds another feature to the anatomy - an ergosphere. The ergosphere resides in an ellipsoidal region outside the outer event horizon. The ergosphere represents the last stable orbit, and the outer boundary is called the static limit. Outside of it, a hypothetical spaceship could maneuver freely. Inside, space-time is warped in such a way that a spaceship would be drawn along by its rotation.

An interesting point that comes up in the case of a spinning black hole is that of the naked singularity. The faster the black hole rotates, the larger the inner event horizon becomes, while the outer event horizon remains the same size. They become the same size when the rotational energy equals the mass energy of the black hole. If the rotational energy were to become more than the mass energy, the event horizons would vanish and what would be left is a "naked singularity" - a black hole whose only part is the singularity.

Yet another distinguishing feature of the Kerr black hole is that, since it rotates, the 0-D point that is the singularity in the Schwarzschild and Reissner-Nordstrøm black hole is spun into a ring of 0 thickness. Interesting theoretical physics can take place around this ring singularity. One consequence is that nothing can actually fall into it unless it approaches along a trajectory along the ring's side. Any other angle and the ring actually produces an antigravity field that repels matter.
Reissner-Nordstrøm Black Holes

A step up is the Reissner-Nordstrøm black hole. It has the singularity and two event horizons. The outer event horizon is a boundary where time and space flip. This means that the singularity is no longer a point in space, but one in time. The inner event horizon flips space-time back to normal.

Kerr Black Holes

A Kerr black hole adds another feature to the anatomy - an ergosphere. The ergosphere resides in an ellipsoidal region outside the outer event horizon. The ergosphere represents the last stable orbit, and the outer boundary is called the static limit. Outside of it, a hypothetical spaceship could maneuver freely. Inside, space-time is warped in such a way that a spaceship would be drawn along by its rotation.

An interesting point that comes up in the case of a spinning black hole is that of the naked singularity. The faster the black hole rotates, the larger the inner event horizon becomes, while the outer event horizon remains the same size. They become the same size when the rotational energy equals the mass energy of the black hole. If the rotational energy were to become more than the mass energy, the event horizons would vanish and what would be left is a "naked singularity" - a black hole whose only part is the singularity.

Yet another distinguishing feature of the Kerr black hole is that, since it rotates, the 0-D point that is the singularity in the Schwarzschild and Reissner-Nordstrøm black hole is spun into a ring of 0 thickness. Interesting theoretical physics can take place around this ring singularity. One consequence is that nothing can actually fall into it unless it approaches along a trajectory along the ring's side. Any other angle and the ring actually produces an antigravity field that repels matter."
http://home.case.edu/~sjr16/advanced/stars_blackhole.html

Maybe your travelling black hole could be a naked singularity? That seems to be the way you describe it.

 

to 2inquisitive:

You have been Googling I can tell, but I will not follow you as I am not really interested in seeing if it is true of false that all Black Holes have jets. (I doubt that they do; however, I may be wrong.) I never mentioned jets, except briefly in reply to your comments on them. Thus, the first sentence of your post below is entirely without foundation. I never said anything about things falling down the "throat" of them either. - All that is your imagination. Your are entirely on your own here, but please refrain from implying, or in following case, almost stating that I did:

Here you also clearly expose your confusion (actually, it is error) about the accretion disk. I will try to explain why the accretion disk forms where it does. Then you may understand that it has essentially nothing to do with the spin of the black hole. (I do not say "absolutely nothing" to do with the black hole spin as I think there is an extremely weak "twist of space" by any spinning mass. This prediction of general relativity (I believe) is the only one not yet confirmed by experimental evidence. - A test is in progress, which will last many years for the small twist to accumulate an observable effect but the effect is so small that it will probably not be possible to measure it.)

What I think you fail to appreciate is that a BH and star pair are co rotating about their center of mass. Thus, each part of the star has angular momentum about that rotation center. The quasar / black hole light sources is not the case I was concerned with in book Dark Visitor or in this post prior to your confusion derailing us. - (My "dark visitor" is only 2.2 solar masses, not even as large a mass as a modestly sized star!)

The rotational center is very close to the typical big black hole of a HB/star pair that makes a quasar; Perhaps even inside the event horizon, if the black hole is big enough. Thus, as the gravitational gradient, perhaps assisted by the spin of the star, not the black hole, strips off some mass from the star, that mass orbits ever faster around the the black hole as it approaches the event horizon of the BH. - just like the ice skater spins faster as she bring her arms down to her sides.

This in-falling mass, the accretion disk, remains basically in the plane of their co-rotation (although as it gets closer and compresses, the heating does make some expansion away from this co-rotation plane. ALL THIS APPLIES EQUALLY WELL TO NON-ROTATING BLACK HOLES. Your idea, quoted above, especially the portion I have made bold, that the rotation of the black hole is causing and or controlling the spin of the accretion disk is entirely WRONG. It is simple conservation of the angular momentum, like the skater mention earlier. The Black Hole’s "polar jets" can have any orientation WRT the accretion disk because the black hole's spin has nothing to do with where the accretion disk forms. - The accretion disk ALWAYS forms in the plane of the original co-rotation. You are simply in error on this, but I hope you understand now.

PS -thanks for the advise that I should read about how "rotating black hole accrets matter," but just now I am busy correcting someones error about this very subject; however, I doubt they will thank me for my trouble as they never have before.

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Billy T,

my response,

Billy T,

Here is where you expose your confusion, Billy T. What you glossed over as 'essentially nothing' is exactly the mechanism by which the accretion disk of a rotating black hole is set into motion. I would think a 'Ph.D' would known more about the Lense-Thirring effect, especially as much as it has been discussed in these forums. The Lense-Thirring effect for slowly rotating bodies with moderate mass, such as the Earth, is very weak. It is not for black holes, however. Space-time, according to GR, is dragged around the rotating black hole strongly. That is the mechanism for the accretion disk's rotation, which rotates very rapidly. Even neutron stars have accretion disks. Any particles entering the accretion disk will be spun around the black hole and its event horizon. You do understand the accretion disk is outside the event horizon, don't you? This is why gas and dust will not be 'eaten' by the event horizon before it is accelerated by the accretion disk. The acceleration heats the gas and dust, causing them to emitt radiation, both EM and particles. Only a small part of the radiation is visible light. The majority of the radiation is in the form of jets that are emitted from the axis of rotation of the accretion disk. Those relativistic jets are what prevent gas from being 'eaten' by falling directly into the event horizon of the black hole, the gas is blown away by the jets. The gas must enter the rotating accretion disk to the side of the central event horizon. Until recently, most of this radiation was thought to be in the x-ray wavelength, but newer study has detected a very large amount of radiation in the radio wavelength. No companion stars are necessary, there are no companion stars in your 'Dark visitor' scenario, so why do you keep bringing quasars and companion stars up?

Next up, how did your 'dark visitor' come to exist with only 2.2 solar masses? It cannot form with only 2.2 solar masses from star collapse. Some neutron stars have more mass that that. A black hole that forms from star collapse must have at least 3 to 5 solar masses. Some theories state that because a rotating black hole radiates energy away from the black hole, it can eventially stop rotating and become a Schwarzchild-like black hole. Can you calculate if the energy lost from a 3 solar-mass Kerr hole can convert it into a 2.2 solar mass Schwarzchild black hole? 'Primordial' black holes formed during the big bang have never been detected and are not thought to exist by most of the modern mainstream physicists who specialize in cosmology.

Billy T,

No, the idea is not mine, it is the scientific explaination of which you seem to be ignorant, Billy T. In a black hole, the polar jets are entirely a consequence of the orientation of the accretion disk. You seem to be confusing the jets from a neutron star with the jets of a black hole. A black hole's jets are theorized to eminate from the portion of the accretion disk near the event horizon. By the way, the event horizon of Kerr black holes is spherical, the accretion disk is not.

 

To 2inquisitive:

Following quote is from astrophysic group, physics dept. NC university’s web site, but I have made a part bold. Nice pictures of their simulations there also. See:
http://wonka.physics.ncsu.edu/~mpowen/

“If the accretor is sufficiently compact (say, a white dwarf, neutron star, or black hole), and the accreting gas contains sufficient angular momentum, it cannot fall directly onto the surface of the accretor and forms a disk of orbiting material called an accretion disk. As this gas orbits, various mechanisms, presumed to be both hydrodynamic and magneto-hydrodynamic in origin*, rob the gas of angular momentum, allowing it to move inward, eventually falling onto the compact object.”

*Note your “spin of black hole” effect (Lense-Thirring effect) is not even mentioned. Also note that instead of being spun up by the Lense-Thirring effect, of the spinning black hole, the accretion gas is actually LOSING angular momentum TO the black hole, mainly via the magnetic field of the black hole. This transfer of angular momentum TO the black hole is how they got their spin. Most of it, for small black holes, was angular momentum of the initial mass which collapsed to form the black hole, but all angular momentum of mass later absorbed is also vectorially added to angular momentum of the black hole. For big black holes, the original spin is relatively unimportant as many stars with different angular momentum have been "eaten."

These experts are doing very sophisticated simulations of the dynamical details of the accretion disk on the super computer at NCU and yet do not even bother to include the mechanism, which you erroneously claim is the basic cause of the rotation of the accretions disk!

Perhaps you should tell them that they have forgotten the basic mechanism, which forms and controls the dynamics of the accretion disk?

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Can you find even one creditable source that even includes your “spin of black hole” AS EVEN PARTICIALLY CAUSING the rotation and formation of the accretions disk? No. That is because the rotation of the accretation disk is simply caused by the conservation of the angular momentum the gas had as part of the co-rotation of the star supplying the gas and the black-hole system. I.e. the "ice skater " effect, as I stated in prior post. I.e. the rotational speed up of the gas as it approaches the black hole is the same conservation of angular momentum exhibited by an ice skater’s rotational speed up when bringing arms to her side. Neither of these increases of rotation rate has anything to do with the spin of a Kerr black hole.

I challenge you to find even one reputable (published in a science journal or by a university's web site) article that even mentions the Lense-Thirring effect as even partially influencing the shape, spin, or formation of the accretion disk. I will visit any site you claim to find. Until you do, stop misleading readers here with this nonsense of yours. It is the simple "ice skater" effect that spins up the accretion disk.

BTW, the polar jets you like to talk about also are not made by your “spin of black hole” effect either. These jets are made my the magnetic field, which although it usually reasonably aligned with the spin because it is related to the spin in most cases, it need not be so aligned.** (Earth and Pulsars discussed more fully in footnote below, are examples of non alignment.) The basic mechanism of the jets is that the MAGNETIC field accelerates electrons out along the poles of the magnetic dipole and charge neutrality requirement drag positive ions along with them.
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**For example, the neutron stars, which we call pulsars simply because by chance their magnet poles point towards Earth twice each rotation, are very highly conductive and when they collapse to form the neutron star the magnetic field that happend to be in them at the time of the collapse is "trapped" and compressed to much greater strength (many orders of magnitude greater). The pulsar's beam is like the black hole's jets, "squrited out" along the magnetic pole axis and some of the production processes (acceleration of the electrons) are identical. Obviously, in this case, the magnetic pole is not aligned with the rotation axis either. I.e. for no pulsar we have observed is the spin and magnetic axis the same! BTW this compression of an original field is how man briefly makes the most intensive fields he has ever produced: You make as strong a field as you can along the axis of a copper pipe which has high explosive surounding it. Obviously any experiment you want to do in this extremely intense magnetic field must be finished before the imploding copper pipe hits and destroys it.

 

Billy T, I have to go out of town now, will respond to your post in more detail later.
Some quick thoughts:
Your link does not work for me. I noticed at their website this abstract. I have been able to open a link to the full paper yet, but are you sure you are not looking at a computer model of particle dynamics based on hydrodynamic simulations for your rebuttal?

Do you know the difference between what is sometimes called the Lense-Thirring effect, frame dragging, gravitomagnetics, and magneto-hydrodynamics? Also, if the particles being spun around the accretion disk did not lose angular momentum, why wouldn't they simply orbit the black hole indefinitely?

 

don't bother with your paper - it does not seem to be on subject. just tested my link and it works fine for me. Yes i know about magneto- hydrodynamics - worked for years on the controlled fusion problem.

Post your own link as I requested and challenged you to. Any reputible source showing anyone believes your view.

 

Billy T, I have read several papers in the past discussing accretion disk dynamics. Just google Lense-Thirring accretion disk and you will find many papers and sites. Here is the first one I visited just now with animations of both the Lense-Thirring precession and gravitomagnetic effects illustrated in computer simulations.
http://research.physics.uiuc.edu/CTA/movies/lt/index.html

From the site:

http://research.physics.uiuc.edu/CTA/news/sidebands/

 

In the limits of a fairly flat neighbourhood (eg your free dust cloud) and long time duration, accretion discs coincide with the equatorial plane of a rotating hole. In more complex systems with multiple significant gravitational sources and/or unusual inflows it is possible to get an initially misaligned accretion disc. Note however that this isn't a minimal energy state so it needs to be maintained. Here are some interesting papers to review:

http://arxiv.org/abs/astro-ph/0602306 - evolution of a BH with initially misaligned accretion disc

http://arxiv.org/abs/astro-ph/0603583 - clumping in the exterior regions of a supermassive BH accretion region

http://hubblesite.org/newscenter/newsdesk/archive/releases/1998/14/text/ - image and description of a BH with misaligned disc.

The Chicken

 

To Magic Chicken (and 2 inqusitive also):

Thanks for the references. From your first’s abstract (with bold added):

“We also allow the direction of the hole spin to move under the action of the disc torques. In such a way, the evolution of the hole-disc system is computed self-consistently. ...”

Note the BH's spin equator MOVES to the co-rotation accretation-disk plane and the accretion disk is NOT formed in the spin plane as 2Q suggests. I said, and still claim, that the accretion disk ALWAYS FORMS IN the plane of the co-rotation of the black hole and the star from which the material of the accretion disk is being stolen.

I also even suggested (prior to Nature paper referenced below) that the means by which the angular momentum of the matter being eaten by the black hole was probably by magnet torque. This view of mine has now also been vindicated. See 10June (I think) Nature paper (Vol 441 p953) with free "on line" summary at:

http://physicsweb.org/articles/news/10/6/10

The "photo" there also shows the accretion disk in plane of co -rotation. I continue to insist that the plane of the accretion disk is always as I said, but now it appears that the “equal and opposite” magnetic torque on the black hole can and does change the angular momentum of the black hole or its spin direction to (it enough material is eaten) bring the black hole’s rotational equator into the plane of the accretion disk. Each time a new star wanders too close to a black hole and is eaten by it the mass gained by the black hole is always coming in via the plane of their co-rotation, which initially with high probability will not be the equatorial rotation plane of the black hole, but if the total angular momentum of the black hole is smaller that the angular momentum being eaten, then the black hole spin equator can be “torqued” to align with the accretion disk. In no case does the accretion disk equator DETERMINE the plane the accretion disk FORMS IN, as 2inquisitive was suggesting, but given the condition I just mentioned, the spin equator can align to agree with the accretion disk plane. Magic Chicken: Do you agree with this bold text? If not why not?

Your second reference is mainly about the gravity waves generated especially in the year or phase of capture, not very relevant to our discussion of how the accretion disk forms and what determines the plain it forms in (My “plane of the co-rotation” vs., 2iqusitives’s “equator of BH spin”)

Your third reference is more to the point. It contains:

“The suspected black hole is so dense it contains the mass of perhaps a billion stars, compacted into a small region of space not much larger than our Solar System.“ - - It is “only suspected” to be a BH because the in-falling mass is so thick near the central regions, (like those of the central black hole suspected to be in our own “milky way galaxy”) that the central region can not be seen by telescopes.

AND:

“Resolving features as small as seven light-years across, Hubble has shown astronomers that the hot gas disk is tilted in a different direction from the black hole's axis — like a wobbly wheel around an axle. The black hole's axis is identified by the orientation of a high-speed jet of material, glowing in X-rays and radio frequencies,”

Which is exactly what I stated: Namely the accretion disk is NOT in the plane of the black hole equator or controlled by the black hole’s spin. In this case (NGC 5128) the black hole is extremely massive and eating whole galaxies, not just individual stars.

Because NGC 5128 is so massive, the angular momentum eaten even in a decade can not significantly change the spin direction of the black hole, so of course the accretion disk is observed to NOT be in the black hole’s equatorial plane. It is, however, interesting that as the galaxy mass being eaten approaches very close to the event horizon it does appear to be “clumping” (to use your references term) and is somewhat out of the co-rotation plane. This is exactly what I would expect* for such a massive black hole. The reaction of the spin of the black hole to the magnetic torque is less than this same torque acting on the that part of the accretion disk close to the EH. This is similar to the dynamics of linear momentum in an inelastic collision between two significantly different masses, M & m. I.e. the percentage momentum change of m is greater than that of M when they are joined as (M+m) mass body, but of course their absolute changes are identical. (The gain of one exactly equals loss of the other to keep system total constant.)
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*Your reference does not include the following idea that occurred to me:
Although an entire galaxy is being eaten by NGC 5128 , it is eaten “one star at a time.” It takes considerable time for enough angular momentum of the in-falling mass to be reduced by the magnetic field torques before the mass can disappear inside the EH. Thus perhaps, each of the “clumps” now visible is the residue of a star (or star pair). If this is the case, perhaps they are relatively little, if any, displaced from their individual “co-rotation” planes. This idea can be tested, in principle, because it predicts that when a very massive black hole is eating a “globular galaxy” the “clumpness” and displacements of the “clumps” from the average “co-rotation plane” of the entire galaxy will be greater than in the case where a “spiral” galaxy is being eaten by a black hole approximately in the plane of the spiral.

 

What about Q0906+6930? A reported 12.7 billion year old recently found black Hole that is estimated to be at least 10 billion (if not bigger) solar masses.

http://www.space.com/scienceastronomy/heavy_blazar_040628.html

Does it have the same nutritional habits as NGC 5128? One star at a time? Or does it like to eat several 'Big Whoppers' in one shot?

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Not an astronomer and know nothing about this BH, but in general I think stars within a galaxy are typically at least a few light years apart, so if the galaxy is "falling" into a typical BH, not the massive giant at the center of a galaxy, and the black hole can eat a star in less than a year, I would think it would typically be "one at a time" with a lot of quasar light produced. This would be the case if the star happend by chance to be approaching the BH with "small impact parameter."

However, I also suspect that it is very rare that the star has a small "impact parameter" for its "collision" with the BH, unless the BH's EH is approaching "galaxy size". Thus for the angular momentum to disappear enough for the star to disappear inside the EH, it may take 10s of thousands of years, especially if the magnetic field of the BH is not strong because this magnetic field is the "handle" that is used to steal the angular momentum from the star and let is spiral inward rather than orbit forever. So I would expect in some cases the partially ripped apart stars number in the dozens and may be the "clumps" in my post.

It also worth noting that the gravity gradient outside the "really big" BH's EH is "really small" so the stars it is eating would not be as much "ripped apart" as they would be if only a modest BH were eating them. This is also a factor. I.e. a "really big" BH may have little or no quasar light for a long time as the star orbits "intact", but slightly elongated towards the BH. These stars are eaten whole without ripping them apart first, so one night from our POV they just "turn off" as they go behind the EH surface, but their last "light" may be only radio waves for us.

I really do not know, but these are my guesses. I hope they are at least reasonable ones.

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Billy T,

Why do you keep bringing up co-rotating blackhole/star systems? The example I was referring to was your isolated 2.2 (?) stellar-mass black hole sneaking through space near our solar system undetected and undetectable, according to your initial statements. You stated interstellar gas and particles would just fall into the black hole without emitting any detectable light or, presumably, radiation or particles of any kind (undetectable, remember?). I stated particles and interstellar gas that would be consumed by the black hole would first rotate around the accretion disk, emitting radiating before moving past the event horizon.

When a black hole initially forms, the accretion disk normally coinsides with the rotational equator of the black hole. Billy T, light and mass cannot escape from inside the event horizon, but gravity can. The rotating mass of the black hole drags spacetime around its orbital plane, the Lense-Thirring effect. This small 'drag' helps insure the accretion disk will align perpendicular to the rotational axis of the mass of the black hole, not form around the polar axis for example. It is your 'ice skater' example of a combination of conservation of angular momentum and the dragging of spacetime around this collapsing event when the black hole is formed. The quote you used was in reference to AGN (active galactic nuclei), supermassive black holes in densely populated areas of galaxy centers. All this additional mass near the black hole can affect the accretion disk and its orientation.

The paper you quoted from describes torgue produced by the Lense-Thirring precession. If the black hole being formed is due to the collapse of a lone star not being affected by large amounts of nearby mass, the torgues from the Lense-Thirring precession and angular momentum should align the accretion disk with the rotational axis of the collapsing star. Again, that is the type of black hole being discussed in your scenario, not AGN's with huge amounts of nearby mass affecting the accretion disk.

Again Billy T, how did your '2.2 stellar-mass' black holes come to exist? Do you still believe they can move through interstellar gas and dust without producing any detectable radiation? Do you believe the 'jets' produced by black holes align perpendicular to the accretion disk, or parallel with the spin axis of the infinity inside the event horizon?

 

To answer first question: Because I think you should admit error and retract idea in your claim that it is the equator of the black hole's spin that determines the plane the accretion disk froms in, etc. See the reference again where cause is stated, especially the new Nature reference that does include magnetic field as a "secondary effect" (in addition to the dominate and controlling gravity effect I spoke of) No one even mentions your "controlling space-spin-torque General Relativity effect", not even people doing very sophisitcated modeling of accretion disk dynamics!

Yes we started out discussing Dark Visitor's 2.2 mass black hole, RAPIDLY MOVING THRU LOW DENSITY INTER STELLAR GAS but you want to erroneously ignore this rapid motion and low density and talk about a black hole stationary wrt a huge mass and the accretion disk that does form in that entirely different situation. I tried to make you understand that if the black hole is going very rapidly thru a low density background of atoms it will just "core out" a cylinder of vacuum thru them eating them all inside the event horizon before they make any new collisions. Without collisions to excite these atoms , they will not radiate. The radiation form an accretion disk is caused by the fact that as the matter spiral in towards the black hole it is compressed and the collision rate enormously increased. This "in-falling" gas in the accretion disk is gaining tremendous* energy from the gravitational field, but if it did not make collisions there would still be no radiation (at least not from neutral atoms and even a neutral plasma, except for very high order effects). Without collisions, the atoms would all stay in their ground states and just orbit faster and faster as they come nearer to the event horizon. The thing you must try to understand is that collisions are the mechanism that converts the gravitational energy the atoms are gaining into radiation.

If the atoms are typically meters apart and the Black hole is coming fast thru them, they do not make any increase in their collision rate before disappearing inside the event horizon. - It is as simple as that. Why can you not understand? - I am tired of explaining it to you, looking up references for you etc. This is the last time I will explain that the fast traveling Dark Visitor physic is entirely different from that of an accretion disk. Read** Dark Visitor book if you need more help with the physics or just admit your were wrong. Also there, in Chapter 8, you will find discussion of several other than Black Hole objects that could be the "dark visitor".

I have explained in a couple of prior posts how and why there may be more small black holes (a few solar masses) than all the stars that have ever existed. Will not repeat all here, but has to do with fact that the always assumed (because even with this assumption the math is very difficult) spherical symetry of stellar collapse is wrong. Each of the 100 to 300 solar mass of the first generation stars probably did not have this perfectly symetric collapse assumed, for mathematical simplicity, but made many smaller black holes in a series of irregular collapse, explosion, and gravitational reassembly of the exploded mass cycles.

The physics of this has to do with the fact stellar fusion rate is very stong function of temperature and only depends upon density quadratically. This produces a self accelerating rate of fusion at some NEAR center location, so the first region to burn all to iron and collapse, very likely is not collapsing exactly at the center of the star. This produces the asymetric explosion, for example, as can still be seen in the expanding Crab Nebular gases (but that left a neutron star behind as the original star was not the 100s of solar masses typical of the young and much smaller universe.)
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*Although the "in-falling" atoms do not lose any mass, they gain so much energy from the gravity field that the radiation can be about 30% (to even 60% ) of what converting their mass to energy by fusion could produce. - I.e tyopically an order of magnitude greater energy than if nuclear fusion were the energy source.

**For free - see instructions at web site under my name.

 

Billy T,

Billy T, I don't admit an error because I don't believe I have made one concerning what I have said about the initial formation of accretion disks. Your references are with respect to black holes feeding off a companion star, thus the accretion disk is aligned with the star being 'eaten'. The Lense-Thirring effect is not a 'magnetic field', but the distortion of spacetime that was present around the lone star even before it collapsed. Maybe you are confusing the gravitomagnetic effect with the Lense-Thirring precession, a tidal effect. They are two sepatate effects. Here is a short explaination of the formation of accretion disks from Wiki. Sources are plentiful.

http://en.wikipedia.org/wiki/Accretion_disk
My question regarding your 2.2 solar mass black hole is in reference to the fact that a collapse retaining only 2.2 solar masses would produce a neutron star, not a black hole. Neutron stars are from 1.4 to 3 solar masses, maybe even more, such as a strange star. It's all still theoretical, but the smallest suspected black holes that have been detected are estimated to be at least 5 solar masses in weight. Black holes seem to be much harder to form than once believed. Astronomers have detected a neutron star that was formed from the collapse of a star that was estimated to have over 40 stellar masses. Most of the outer regions of the star is suspected to have been blown off during the collapse that created the neutron star.
http://www.space.com/scienceastronomy/051102_neutron_star.html

Our solar system is presently moving through a cloud of helium gas 60 light years in diameter, as it has been doing for a very long time. The density of the helium is one atom per 10 centimeters cubed, not real dense, but not 'meters apart'. Our solar system is filled with particles from the solar wind emitted from the sun, in addition to the interstellar wind (the helium plus other gas and dust) blowing throught it. The 'solar system' extends out far beyond the orbits of Pluto and the Oort cloud, where there is a region called 'termination shock' where ions and gas are concentrated. There is much more matter in interstellar space than once thought. Black holes have been detected many thousands of light years from Earth, even when they were quite and not actively 'feeding'. They give off much, much more radiation and magnetic fields than once thought. Again, I do not believe a black hole could be nearby without our satellites and ground-based observatories detecting it in some wavelength. I have never seen any modern reference suggesting gas could simply fall straight into a black holes event horizon without orbiting around the accretion disk first. Do you have a reference? (Just asking, as I haven't read of this before) The modern references I have read estimate that only 30% to 50% of matter accreted by a black hole actually passes through the event horizon, the rest blown off by the jets eminating from around the inner part of the accretion disk near the event horizon. Magnetic fields are now thought to rob some of the particles (I assume mostly ions) in the accretion disk of angular momentum, heating the particles until they glow brightly in x-ray radiation, for example. Particle collisions within the accretion disk is not necessary for heat and radiation to be emitted from the disks. Black holes are much more complicated than they were once thought to be, much more is happening in the areas surrounding the event horizon that we can detect.

 

True. Most forms of life will be very uncomfortable by about that time. There's actually a very short window for complex life. But we'll probably be long extinct by then.

As for the fate of our solar system there is a much more interesting detail to consider. In 3 billion years our galaxy will undergo collision with another galaxy. Then it will become a combined irreuglar galaxy with tails and such. And then it will become an elliptical galaxy. There won't be many (if any) stellar collisions, but the whole process will dramatically change the nature of our galaxy and the possible kinds of stars it will produce.

Here's a good link:
http://www.cita.utoronto.ca/~dubinski/tflops/

 

It could get very interesting at that time if the supermassive black holes that are supposedly at the cores of our galaxy and Andromeda's for some obvious gravitational reason, 'merge'? If that happens (and I'm not saying it will), Rock 'n' Roll baby

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