From Daily TechThe Milky Way’s black hole is causing a mess, but isn’t gobbling matter as fast as was thought
One of the most complex and intriguing astrophysical phenomenon is the supermassive black hole. A superdense cluster of mass, the supermassive black hole gobbles up surrounding matter, sucking it into its gravity well. Despite the tremendous importance of these celestial bodies to the structure of our universe, scientists still remain confused about specifics of how they operate.
Supermassive black holes help to shape our universe, but their behavior is still poorly understood
. (Source: PureInsight.org)
It is a well known fact that there is a supermassive black hole at the center of our galaxy, the Milky Way. Dubbed Sagittarius A* (Sgr A*), the black hole is rather weak, due to its inability to successfully capture significant mass. The black hole is bordered by dozens of young stars. It pulls gas off these stars, but is only able to suck in a small percentage of this high velocity stream.
Past estimates put its consumption rate at a mere 1 percent of the gas it pulls away from the stars. Now a new study, using data garnered from the NASA’s Chandra X-ray Observatory, has determined that the black hole is likely eating far less than that figure even — new models indicate it to be consuming a mere 0.01 percent of the gas it sucks off.
Read the rest of the story here.
mikelorrey (15:23:36) :
Interesting images, thanks Mike.
Whatever is in the middle looks pretty bright though. 🙂
tallbloke
2010/01/09 at 4:14pm
“Interesting images, thanks Mike.
Whatever is in the middle looks pretty bright though. :-)”
I suspect that bright spot is either a star getting sucked in (I think that image is of a galactic core supermassive black hole) or is the hawking radiation at the event horizon, as I believe this is an IR image.
Mike D. yeah, “flat universer” at your service.
Mike Lorrey, picture one, the donut, is a natural shape formed by plasma which is reproducible in the lab.
http://elikelehan.artician.com/portfolio/plasma-donut/
Picture 2, a collated beam of x-rays and electrons you can do this one at home.
http://nursemyra.wordpress.com/2009/01/27/how-to-make-your-own-x-ray-machine/
So given that these observations of mysteries of the universe can be knocked up in your own garage by what logic are black holes and any other invisible entities needed?
Keith, those pictures are of cosmological structures hundreds or in the case of the second, tens of thousands of light years wide. Given the scale, the amount of energy involved in moving that much mass that energetically forces the driving entity to exist extremely far down a very very deep gravity well, far deeper than a neutron star. A supermassive black hole has a mass in the hundreds of thousands to millions of solar masses. Now, if you are capable, try calculating what the gravitational force will be vs the forces keeping neutrons separate. Calculate what the gravitational acceleration is and the terminal velocity is at the event horizon vs light speed. Try doing some math before spouting off.
The images provided in the above comment contradict the “black hole” theory in that originally at least, nothing could escape “black hole” gravity field. Obviously, plenty is escaping. And, once the escaping energy and matter was too common to ignore, ad hocs were layered onto the original model.
Regarding the second image, the cigar galaxy, it is consistent with how plasmoids act in the laboratory, energy and matter are drawn into the galactic center in plasma flows which can be observed & measured by their magnetic signature and build up, at some unknown threshold the energy is ejected out along the polar axis, notice the radio lobe on the bottom half of the image.
Dr. Svalgaard wants to keep the focus on my opinion, but Dr. Morris’ statement stands on its own:
“We know the galactic center has a strong magnetic field that is highly ordered and that the magnetic field lines are oriented perpendicular to the plane of the galaxy,” — Dr. Mark Morris, UCLA professor of physics and astronomy
And, again, Dr. Svalgaard wants to put the focus on my opinion reagarding plasmoids, but it is Dr. Winston H. Bostick that did the work and published the paper. And, it is Dr. Anthony L. Peratt of the Los Alamos National Laboratory that did the work and published papers regarding plasmoids as galactic phenomenon.
DirkH (15:11:58)
Yes, Crothers has done work that strongly suggests there is no theoretical, mathematical underpinning for so-called “black holes”.
It was a concept that people wanted to believe in so they made up mathematical models to support their beliefs. This is called a priori assumptions controlling the construct and then searching for observations that back up the assumptions.
Axiom, then plug in observations that back up the axiom.
Mathematics is essential in quantifying physical relationships of energy and matter, but if disconnected from rigorous observation & measurement like “string theory” is, then it is a dangerous delusion which gives credibility where none is deserved, similar to the many mathematical models used in climate computer models.
To be concise: Garbage in equals garbage out.
But why is this post and comment section relevant to climate science?
It demonstrates the danger of consensus thinking in the sciences.
Once enough people in the community “agree”, even on a clearly erroneous idea, it is very hard to dispel the idea because people have established careers, grant money, and professional ego based on that idea.
Obviously, these people will be hard pressed to give up the idea.
And in astronomy where everything is observed & measured at a distance — long distance, and interpretation & analysis is hard to objectively contradict, it is doubly hard to dislodge.
This danger should promote a high degree of reasonable scepticism and a willingness to keep an open-mind to alternative ideas, but on the contrary as can be seen, here, in this comment section, those that should be the most conscious of these dangers are the most preemptive and dismissive.
How much is this like the climate scientists at the CRU?
Strikingly similar.
James F. Evans
2010/01/09 at 5:31pm
“The images provided in the above comment contradict the “black hole” theory in that originally at least, nothing could escape “black hole” gravity field. Obviously, plenty is escaping.”
OBVIOUSLY, you dont understand what is meant by a black hole gravity field. It is quite possible to escape a black hole’s gravity field while outside its event horizon. The event horizon exists because it delineates the point at which light cannot escape. Light outside the event horizon can escape it just fine.
Tenuc (02:51:07) : well said.
Those pictures are images, they don’t come annotated with forces or even how much mass is in there. if I can reproduce the same morphological structure using charged particles in my garage without the aid of gravity, or a pet black hole to provide some. Then your statement about it needing a lot of gravity to make a shape that big is proven false.
Plasma structures scale over magnitudes of 10^14 or more, so its perfectly do-able.
mikelorrey: I estimated the calculation that you suggested, the amount of gravity it would need to pull that amount of matter into that shape is for all practical purposes zero.
My knowledge of gravity, based upon observing a falling apple, leads me to believe that the only shapes it will produce are straight lines. Two apples next to each other will have minimal effect on each other, so they will not make any interesting shapes by spiralling around each other as they fall.
In the gravity model where would the singualrity be to make this shape? http://commons.wikimedia.org/wiki/File:Cygnus-loop.gif#file
Charged particles in plasma on the other hand do spiral around each other as they move. My knowledge of electric and magnetic fields, and the observations as to what shapes plasma can make in the presence of electric fields, give many interesting shapes.
For example, currents do not ever just flow through space with a homogeneous density. Particles in the solar wind for example do not move in a straight line. It is more efficient for them to coalesce into filaments that twist around each other. This coalescence can accrete matter and the matter can be observed to show you the shape of the fields, as seen in the Cynus Loop above. In the gravity model where would the singualrity be to make this shape?
If further proof was needed, again where is the gravitational signularity that forms this shape? It’s a helix for goodness sake, and it does not have a centre. Please dont tell me that this must be a fortuitous result of Dark Matter.
http://www.everythingselectric.com/images/the-double-helix-nebula-birkeland-current-banner.jpg
One question to the illuminati: Is it possible that light suffers a redshift when it escapes a deep gravity well (i.e. one that can still be escaped)?
“Is it possible that light suffers a redshift when it escapes a deep gravity well (i.e. one that can still be escaped)?”
Ok, found it, yes it does:
http://calgary.rasc.ca/redshift.htm
photon without a Higgs (15:58:27) : Hey, that thing how is it manage to eat and defecate at the same time through the same hole?
Just cool it down!, what common sense tell us is that as above so below, do not entangle the universe with your entangled ideas and so sophisticated and cool inventions. There are no other thing that logically a series of three dimensional universes…more than three dimensions, ya know, it´s pure witchcraft, it is the phantom´s realm, kind of new age “The teachings of Don Juan”, beware! you could end up in the asylum.
JonesII (18:51:16) :
It isn’t clear what you are saying.
mikelorrey (17:39:25) wrote: “…you [Evans] dont understand what is meant by a black hole gravity field.”
Yes, I understand the theory and the so-called “event horizon” and all that.
But a gravity field not quite strong enough to suck in light (the area just beyond the supposed “event horizon”) would still have tremendous forces of gravity pulling into the “black hole”, this gravity field would disrupt most if not all organized energy and matter structures.
But as Dr. Mark Morris, UCLA professor of physics and astronomy, so eloquently points out there is substantial structure in this region, “We know the galactic center has a strong magnetic field that is highly ordered and that the magnetic field lines are oriented perpendicular to the plane of the galaxy”, and a “black hole’s” supposed existence is entirely based on mathematical equations, one needs to explain the energy and matter relaionships of these structures mathematically.
On the contrary, there is no mathematical formula that explains these magnetic stuctures so close to the supposed “event horizon” or any mathematical equations expressing energy and matter relationships that explain the ejection of all this energy and matter from areas “in front” of the supposed “event horizon”. As astromers like to say, “it’s all hand waving and word salad.”
You know, live by the mathematical sword, die by the mathematical sword.
And remember, electromotive force is 39 orders of magnitude stronger than gravity.
Gravity is weak in comparison, that is why mathematicians jump the density of a “black hole” up to infinity to make their model work.
(Science doesn’t even know what stength of gravity is needed to overpower light or if it can be done at all — it’s all naked theoretics without any supporting physical confirmation — flying without a plane with wings, if you will.)
And, by the way, since “infinity” can’t be quantified — it goes on forever — and “infinity” is intrinsic in the mathematical definition of a “black hole”, a so-called “black hole” can’t be quantified.
So violates all requirements that mathematics when applied to natural forces, actually quantify those natural forces.
So-called “black holes” are as much, if not more, a hoax than AGW.
Both rest on the desired perception of men, not empirical science.
I usually don’t like to quote wikipedia, but this logic seems to be pretty sound (assuming the references actually support the statements, of course):
* The star S2 follows an elliptical orbit with a period of 15.2 years and a pericenter (closest distance) of 17 light hours from the center of the central object.[9]
* From the motion of star S2, we estimate the object’s mass as 4.1 million solar masses.[10]
* We also know that the radius of the central object is significantly less than 17 light hours, because otherwise, S2 would either collide with it or be ripped apart by tidal forces. In fact, recent observations[11] indicate that the radius is no more than 6.25 light-hours, about the diameter of Uranus’ orbit.
* The only known object which can pack 4.1 million solar masses into a volume that small is a black hole.
http://en.wikipedia.org/wiki/Supermassive_black_hole
BTW: an interesting alternative idea to black holes (not the existence of highly compact astrophysical objects, just the prediction of GR of a singularity and its associated event horizon) was presented in a paper at the Texas Conference on Relativistic Astrophysics at Stanford in Dec of 2004 by George Chapline of Lawrence Livermore National Laboratory (http://arxiv.org/ftp/astro-ph/papers/0503/0503200.pdf). The prediction is that these objects are actually Dark Energy Stars. Here is an article in NewScientist about Dark Energy Stars: http://www.newscientist.com/article/mg18925423.600-three-cosmic-enigmas-one-audacious-answer.html, and here is an interview with Dr. Chapline on the topic: http://www.universetoday.com/2006/04/11/podcast-dark-energy-stars/. What I like about his theory is that it makes testable predictions which can easily falsify the theory. I don’t detect any pseudo-science here, but what do I know – I’m not a physicist.
RE: ( Leif Svalgaard (13:28:26) ) – I understand that you’re a practicing scientist and so it may be difficult to convey your knowledge without resorting to the mathematical details when you’re frustrated by pseudo-scientific nonsense, but dazzling us with math-speak only reminds me of the note a pastor taped to his lectern: “When you get to the weak part of the sermon, pound harder and shout louder.” The posts of James F. Evans do not persuade me that he understands deeply the physical theories and has carefully weighed the options for each, but rather is only persuaded by the rhetoric of others. That doesn’t mean he is wrong – I am just not persuaded by his arguments. However, I think I do have some familiarity at a general philosophical level with the concepts you are speaking of, and I think I should point out that one need not accept that the mathematical constructs of the theory of General Relativity, such as Minkowski spacetime, actually correspond to entities in the real world. The ontology of GR is still quite a hot topic of debate amongst philosophers of science – many of whom are physicists who have put in the years needed to understand the math. It may just turn out that Minkowski spacetime is just a convenient way to do the math. If that is the case, then maybe singularities do not actually exist in the real world, in which case the massive, compact astrophysical objects – which certainly do exist in the real world and which we currently call “Black Holes” – may be something else entirely different… maybe they are Dark Energy Stars? Who knows? But it is exciting to know that there are such intriguing theories for areas of science that are so often presented as “settled” to the lay public.
An enlightening tome on the subject of the ontology of Relativity is “Time and the Metaphysics of Relativity”, http://books.google.com/books?id=EY8KVI-05P0C&pg=PA79&lpg=PA79&dq=einstein+relativity+and+absolute+simultaneity&source=bl&ots=SMtaJPZaAf&sig=EyR5Dl6afyOh7ZwxGTrz9Ue8XG4&hl=en&ei=9UxJS47qOpOmswOI_MDmBw&sa=X&oi=book_result&ct=result&resnum=10&ved=0CDAQ6AEwCQ#v=onepage&q=einstein%20relativity%20and%20absolute%20simultaneity&f=false.
James F. Evans (12:49:00) :
But when he steps out of his specialty
I worked ten years at “The Institute for Plasma Research” at Stanford University…So space plasma physics IS my specialty. My colleagues were Oscar Buneman, Peter Sturrock, John Wilcox [look them up] among others.
What is branch of plasma physics is your specialty field?
James F. Evans (17:31:39) :
Dr. Morris’ statement stands on its own:
“We know the galactic center has a strong magnetic field that is highly ordered and that the magnetic field lines are oriented perpendicular to the plane of the galaxy,” — Dr. Mark Morris, UCLA professor of physics and astronomy
Nothing wrong with that statement, and nothing surprising either. And ‘strong’ is relative. The field is millions of times weaker than a sunspot’s.
What is wrong is your notion of ‘intense magnetic fields’ and plasmoids and non-gravity universes and all the rest of the nonsense. Combined with being learning-resistant.
Leif Svalgaard (13:28:26) :
James F. Evans (12:26:33) :
Anybody, who knows anything about the scientific discussion of so-called “dark matter” or “dark energy” and responds in good faith, knows that a vigorous debate rages in scientific circles about the existence of “dark matter” and “dark energy”
The debate is not about the existence, but about the nature of dark matter. As I have commented, dark matter can be [and has been] observed and mapped by gravitational lensing.
James F. Evans (12:26:33) :
It’s an evasive answer because as Dr. Svalgaard knows a “singularity” is a mathematical construct.
Me: “Everything in physics is at the bottom mathematical constructs. followed by long description of singularity …
You went strangely quiet on asking for a description, so i take it that my replay was satisfactory. At any rate, my reply was close to how physicists actually describe and understand these things. So there you have it. Now, I’m waiting for your description of an electron…
JonesII (18:51:16) :
“what common sense tell us…
It seems that common sense is not so common…
tallbloke (15:09:25) :
Leif Svalgaard (14:34:26) :
tallbloke (14:03:17) :
“Not quite good enough.”
It’ll have to do, my reply has been binned.
If you could behave civilly, your voice could have been heard and we would have enlightened. Now you hide [equals zero credibility in my book].
Patrick (20:06:22) :
RE: ( Leif Svalgaard (13:28:26) ) – I understand that you’re a practicing scientist and so it may be difficult to convey your knowledge without resorting to the mathematical details when you’re frustrated by pseudo-scientific nonsense, but dazzling us with math-speak only reminds me of the note a pastor taped to his lectern: “When you get to the weak part of the sermon, pound harder and shout louder.”
I’m not frustrated and it is not difficult to convey these things. I have always said that if you really understand something, you can explain it to a six-year old. I had given Evans the change to specify what level of description he had in mind. Since he was unresponsive to that, I simply resorted to the terms we physicists normally use [not all use the same formalism] in describing such matter. This description is highly mathematical, but the math describes reality very well. I could probably in book of a thousand pages give a description that he might understand [actually Roger Penrose has already done that: “The Road to Reality”, 1100 pages], but it would be completely wasted as I’m convinced that Evans really didn’t want to learn about singularities, black holes, etc, simply because those things clash with what he believes, e.g. that “Astronomers cling to outdated ideas”.
Patrick (20:06:22) :
But it is exciting to know that there are such intriguing theories for areas of science that are so often presented as “settled” to the lay public.
Scientists are always probing the outer edge of what they think they know and that is how progress in eventually made, but as anna v pointed out, you need to know the lay of the land first before you can extend the frontier.
Dr. Svalaard, such a long explanation in the face of such limited empirical observation & measurement is not persuasive. It seems more like a cover and distraction from the the limited observations & measurements available.
In law, it would be seen as overstating the case.
Dr. Svalgaard wrote: “[Evans’] non-gravity universes…”
No, I never stated that gravity doesn’t have a role in the Universe.
Gravity does have a role along with electromagnetic forces.
Actually, Hannes Alfven had a good quote along these lines: “Gravitational systems are the ashes of prior electrical systems.”
And, considering the relative strength of gravity versus the electromotive force, Alfven makes sense.
James F. Evans (21:45:15) :
such a long explanation in the face of such limited empirical observation & measurement is not persuasive.
The description of spacetime [and its consequences] are based on a large body of exquisite experiments and observations. General Relativity has passed every test we have put it too. ‘Persuasive’? It is about your understanding, not persuasion. Now, there were several other questions I had put to you. Do I really have to repeat them?
Dr. Svalgaard wrote: “The debate is not about the existence, but about the nature of dark matter.”
I’ve read enough reports and reviewed papers to know that the above statement is misleading, plenty of physicists question the existence of “dark matter”, and if the nature of “dark matter” can’t be determined, then there is question as to whether it exists at all.
James F. Evans (22:32:14) :
the nature of “dark matter” can’t be determined, then there is question as to whether it exists at all.
We don’t know the nature of mass, yet there is no question [in my mind at least] that mass exists.
At any rate, the effect of dark matter has been directly observed, so we have now to try to figure out what its nature is. This may be as difficult as figuring out what mass is.
Leif Svalgaard (20:52:55) :
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Yeah, me too – I just thought it would be kinda rude to throw that out there on top of my other criticism. But I understand now the point you were trying to make.
However, I do think an insistence of, for example, the existence of Minkowskian spacetime or relative simultaneity just because GR (and STR) have been “proven” empirically, is where physicists overstate their case. As I understand it, there are other ways of understanding the ontology of the Lorentz Transformations which form the core of Einstein’s relativity, and the same empirical facts support both. That is, until Bell’s inequalities were experimentally violated by Aspect et. al. In perhaps a naive and simplistic understanding, absolute simultaneity appears to violate the restriction on faster than light causality assumed by STR. Of course, really smart people are working on reconciling this new data with what has been up ’til now an amazingly successful theory, but to a non-mathematical, naive lay person like myself, it would seem to be very much an open question as to whether or not Minkowskian spacetime and relative simultaneity really are the best way to describe reality, or if, perhaps, they are rather convenient instrumentalisms for theorists.
Leif Svalgaard (12:26:54) :
It seems that on the largest scales, our universe is dominated by repulsive forces causing the expansion to accelerate.
tallbloke (12:32:59) :
What is the physical mechanism proposed for this repulsive force Leif?
Leif Svalgaard (13:45:20) :
At this point is mainly an observational fact. But people are working on it 🙂 We have to go [like it or not] where the observations lead us.
tallbloke (14:03:17) :
We can agree to disagree about whether the conditions for something being regarded as an ‘observation’ have been met here. However, my conclusion is that there is no conceivable repulsive force accelerating a universal expansion and we are being led up the garden path of Big Bang Bung here.
Maybe the turtle is on ice skates and has pulled it’s legs in. 🙂
Leif Svalgaard (14:34:26) :
Not quite good enough. Take the specific papers [some referred to upthread] and criticize them as why they do not meet the conditions. Clearly you must have read these already, otherwise you cannot pontificate on whether they describe observations.
tallbloke (15:09:25) :
“Not quite good enough.”
It’ll have to do, my reply has been binned.
Leif Svalgaard (20:37:45) :
If you could behave civilly, your voice could have been heard and we would have enlightened. Now you hide [equals zero credibility in my book].
tallbloke :
I haven’t been hiding, I went to sleep as it was late here. And I did behave civilly, my response was; “you cannot pontificate” I wouldn’t dream of trying to emulate your speciality 😉 complete with winky smiley. Humour and brevity seemed appropriate. I’ll give you the long version now in carefully chosen words.
The danger with consensus science, as James F. Evans pointed out above, is that we end up with nonsense like co2 driven climatology. Cosmological hypotheses used to jostle for position, with different possible explanations for the weird and wonderful phenomena we observe far out in space swapping positions with each new discovery. Now, we have an entrenched dogma which holds sway by shouting down or censoring alternative interpretations with appeals to authority, official positions and defamation of proponents with accusations of heresy. This is the real pontification, because it the creation of a false papal infallibility. The news is, all cosmological theories are speculative. They are interesting, informative, and of benefit, provided that no-one is foolish enough to take any single theory as being sufficiently well grounded that it can legitimately be used to dismiss alternative interpretations of phenomena whose nature is still unknown.
Some people prefer the certainty of assumption, others prefer the uncertainty of exploration and adventure. Each of these two approaches should provide checks and balances to the other. On this blog the institutionalized dogmas of consensus cosmology and climatology are both getting the periodic shake-up all sciences need from time to time.
Everyone here, including you, should be able to live with that without resort to accusations of pseudoscience, zero credibility or any other unpleasantness.
Have a nice day.
Leif Svalgaard (22:16:52) :
The description of spacetime [and its consequences] are based on a large body of exquisite experiments and observations. General Relativity has passed every test we have put it too. (…)
Yet, one thing I liked from General Relativity is the concept of the curvature of spacetime, and the thought model of heading out on a straight course from wherever and eventually ending up right where you started from.
Yet based on the WMAP measurements, the geometry appears flat, with no curvature, to within a 2% error margin.
I had mused that everything moving outward from the Big Bang at an increasing rate, leading to an ever-expanding universe, was really not that much of a problem. Since by the curvature, wouldn’t everything just end up back at the starting point anyway? Insufficient mass for gravity to lead to the Big Crunch didn’t matter, because while the mass was rushing apart it was also rushing together.
Still, we are only aware of so much of our universe, with more of it being revealed as the photons of other areas finally reach us. And to an ant on the inside surface of a spherical shell the size of a planet, only aware of what might be within a meter around it, the surface does indeed seem flat. So the hope remains that this universe is not a one-shot event.
James F. Evans (22:32:14) :
Dr. Svalgaard wrote: “The debate is not about the existence, but about the nature of dark matter.”
I’ve read enough reports and reviewed papers to know that the above statement is misleading…
Uh-oh. Is this another “the science is settled — there’s no more need to debate” thang?