David Levy Posted December 28, 2015 Author Share Posted December 28, 2015 (edited) Certainly large, centrally-located black holes will merge, and when galaxies merge their central large-mass black holes will also merge, but that does not add up to a million solar masses. How do we know that black holes can merge? Do we have any evidence for that? Actually, a collision between two spiral galaxies (at a similar size) should eject to space significant amount of their stellar mass. So, technically, (if we accept the idea of black hole merging), there will be a new merged galaxy with double size of BH but with much less stellar mass. This could violet the following proportional: "Each bulge contains a central black hole, whose mass is proportional to the bulge stellar mass 1–5 , MBH ≈ 0.001Mbulge. Therefore, could it be that the idea of merging galaxies isn't feasible? Galaxies do not continue to grow because they are limited to the amount of matter in their vicinity. A galaxy's mass is limited to local matter. There is not matter flowing into galaxies from the great voids between galaxies. Fully agree. However, There is a solid proof that the B.H and stars are growing together. "most massive galaxies in the universe and the supermassive black holes at their hearts grew together over time." So, if There is not matter flowing into galaxies from the great voids between galaxies, How could it be that the B.H increase its size on a daily basis while the stellar mass in the galaxy is also growing proportional to the B.H size? Somehow, the B.H is increasing its size without "eating" the stellar mass of the galaxy. What could be the scource for that new matter (for the B.H and for the stellar mass)? Edited December 28, 2015 by David Levy Link to comment Share on other sites More sharing options...
Strange Posted December 28, 2015 Share Posted December 28, 2015 How do we know that black holes can merge? From the theory that describes black holes. Do we have any evidence for that? Not yet. Actually, a collision between two spiral galaxies (at a similar size) should eject to space significant amount of their stellar mass. Citation needed. Or is this something else you have made up to try and support your ideas? Therefore, could it be that the idea of merging galaxies isn't feasible? So we should abandon all the observational evidence because you made something up? How could it be that the B.H increase its size on a daily basis while the stellar mass in the galaxy is also growing proportional to the B.H size? Somehow, the B.H is increasing its size without "eating" the stellar mass of the galaxy. There is a range of ratios for the mass of black hole and galaxy, so there is no conflict here. "in disk-dominated galaxies, particularly at low mass, there is no tight correlation between MBH and properties of the galaxy." http://www.nature.com/ncomms/journal/v3/n12/full/ncomms2314.html Link to comment Share on other sites More sharing options...
David Levy Posted December 28, 2015 Author Share Posted December 28, 2015 Citation needed. Or is this something else you have made up to try and support your ideas? Please see the following photos. http://www.easynotecards.com/uploads/1175/86/_6ea8c384_144fee962ba__8000_00000610.jpg http://www.wolaver.org/Space/galaxycollision.jpg http://www.spaceanswers.com/wp-content/uploads/2013/01/Black-holes-collide.jpg https://fsmedia.imgix.net/ee/4a/b8/00/990f/4ff6/bc33/e2f0101d8247/an-illustration-of-two-spiral-galaxies-with-their-black-holes-on-a-collision-course.jpeg?w=700&dpr=1&auto=format&q=75 It's looks to me that significant amount of the stellar mass had been ejected to space. Link to comment Share on other sites More sharing options...
Strange Posted December 28, 2015 Share Posted December 28, 2015 Please see the following photos. http://www.easynotecards.com/uploads/1175/86/_6ea8c384_144fee962ba__8000_00000610.jpg http://www.wolaver.org/Space/galaxycollision.jpg http://www.spaceanswers.com/wp-content/uploads/2013/01/Black-holes-collide.jpg https://fsmedia.imgix.net/ee/4a/b8/00/990f/4ff6/bc33/e2f0101d8247/an-illustration-of-two-spiral-galaxies-with-their-black-holes-on-a-collision-course.jpeg?w=700&dpr=1&auto=format&q=75 It's looks to me that significant amount of the stellar mass had been ejected to space. So you have no data to support your claim. In that case, as you made it up, we can safely assume it is wrong (based on past experience). Link to comment Share on other sites More sharing options...
David Levy Posted December 28, 2015 Author Share Posted December 28, 2015 So you have no data to support your claim. In that case, as you made it up, we can safely assume it is wrong (based on past experience). Why? Why don't you accept those photos? The image is very clear. Link to comment Share on other sites More sharing options...
Strange Posted December 28, 2015 Share Posted December 28, 2015 Why? Why don't you accept those photos? The image is very clear. Photos (by themselves) are not data. You cannot tell if matter is being ejected from the galaxy from those pictures. And you certainly can't tell how much. If you think otherwise, please show, in appropriate mathematical detail, what analysis you have done and what results you have come up with. Ideally, you will also provide some peer reviewed papers that agree with your calculations. More generally, you need to get away from "it looks like" as a form of argument. You also need to get away from sweeping generalizations based on the titles of papers and popular articles. Only then will you stop looking foolish. 1 Link to comment Share on other sites More sharing options...
MigL Posted December 28, 2015 Share Posted December 28, 2015 Big Bang nucleosynthesis that created all the Hydrogen and most of present day Helium, took place within minutes of the BB event, Airbrush. But at any time after the inflationary period, the mass energy of the Universe would have been incredibly smooth, such that even today, after 13.7 Bil yrs, the CMB is smooth to one part in ten thousand. It would have taken time for stars and galaxies to form. There would not have been a gravitational attractor strong enough to 'cause' an immediate Black Hole. Link to comment Share on other sites More sharing options...
David Levy Posted January 1, 2016 Author Share Posted January 1, 2016 (edited) http://www.scienceda...90202175320.htm "A pair of astronomers from Texas and Germany have used a telescope at The University of Texas at Austin's McDonald Observatory together with Hubble Space Telescope and many other telescopes around the world to uncover new evidence that the largest, most massive galaxies in the universe and the supermassive black holes at their hearts grew together over time." Hence, please advice if you agree with the following: 1. Galaxies and supper massive black hole grew together over time. 2. There is no need for galaxies collision in order to increase the size of a galaxy. 3. The Milky Way galaxy is growing together with its black hole. 4. In the past, the Milky Way was quite smaller in its size (as well as its black hole). Is there any way to verify the growing rate of the Milky Way? If so, we can technically calculate what was the real size of the Milky in the past - let's say 10 billion years ago (assuming that there were no collision with any other galaxy). Edited January 1, 2016 by David Levy Link to comment Share on other sites More sharing options...
Strange Posted January 1, 2016 Share Posted January 1, 2016 (edited) 2. There is no need for galaxies collision in order to increase the size of a galaxy.. The paper is all about evidence confirming the merging of galaxies and their black holes. That is how galaxies grow. http://iopscience.iop.org/article/10.1088/0004-637X/691/2/L142/meta It is also about elliptical galaxies and therefore not relevant to our galaxy. You really should read more than the title of these articles. Edited January 1, 2016 by Strange Link to comment Share on other sites More sharing options...
Airbrush Posted January 1, 2016 Share Posted January 1, 2016 (edited) The way galaxies grow is through mergers with local galaxies. Early galaxies have active supermassive black holes, quasars, that grow from the inflow of surrounding gas and dust. However black holes are very messy eaters, most of the matter flowing into SBH gets blasted out on the polar jets. So no matter how you look at it, there is simply not enough matter to account for SBH that are over a million solar masses. They got their mass early on, when matter was that close together, long before the cosmic dark ages ended with the birth of the first generation of stars which occurred hundreds of millions of years after the big bang. Edited January 1, 2016 by Airbrush Link to comment Share on other sites More sharing options...
David Levy Posted January 1, 2016 Author Share Posted January 1, 2016 I don't know the current state of the science related to this. I have heard suggestions that black holes might have "seeded" the formation of the galaxy (and then grown) or it might have been created after the galaxy formed. So what is unknown is how black holes can grow to be so massive. But it doesn't seem to be very relevant to the formation of galaxies. I still wander how it could be that we don't know. How could it be that we are so clever to have deep visibility of the first second after the big bang, but we have no idea what came first. Especially, as it is there, infront of our eyes. Link to comment Share on other sites More sharing options...
Strange Posted January 1, 2016 Share Posted January 1, 2016 I still wander how it could be that we don't know. How could it be that we are so clever to have deep visibility of the first second after the big bang, but we have no idea what came first. Especially, as it is there, infront of our eyes. Perhaps because science has much higher standards of evidence than you do. Link to comment Share on other sites More sharing options...
David Levy Posted January 2, 2016 Author Share Posted January 2, 2016 (edited) The paper is all about evidence confirming the merging of galaxies and their black holes. That is how galaxies grow. http://iopscience.iop.org/article/10.1088/0004-637X/691/2/L142/meta It is also about elliptical galaxies and therefore not relevant to our galaxy. You really should read more than the title of these articles. Thanks I'm not sure that I fully understand why it is stated: http://www.scienceda...90202175320.htm "... the largest, most massive galaxies in the universe and the supermassive black holes at their hearts grew together over time." Why they claim that the galaxies and the suppermassive black holes grew together over time? Based on what evidences? In the articale which you have pointed it is stated: http://iopscience.iop.org/article/10.1088/0004-637X/691/2/L142/meta "Research on supermassive black holes (BHs) in galaxy nuclei centers on the growing evidence that BH growth and galaxy evolution are connected (Ho 2004)." But they do not give any further explanation about the idea that suppermassive black holes grew together over time. They mainly focus on the impact of light deficits Ldef: "This Letter reports tight mutual correlations between M•, σ, and the light deficits Ldef that define cores in elliptical galaxies. These point more directly to formation processes. In particular, we find a correlation between the fundamental observables Ldef and σ that is as tight as the well-known M• – σ correlation" But I still do not see a conection between this light deficits to the statement that suppermassive black holes grew together over time. It is also stated: "To set the stage, we recall that it is difficult to understand how cores can form in galaxies that are made by major mergers." So, without getting deep into the merging process, what is the key evidence for the idea that suppermassive black holes grew together over time? Why they also use the word "grew"? In the dictionary it is stated: "undergo natural development by increasing in size and changing physically (of a living thing)" Galaxy is not a living thing. So why grew? Why not: increase, enlarge or become great. Edited January 2, 2016 by David Levy Link to comment Share on other sites More sharing options...
Strange Posted January 2, 2016 Share Posted January 2, 2016 So, without getting deep into the merging process, what is the key evidence for the idea that suppermassive black holes grew together over time? This is mainly based, as far as I know, on the observed correlation between black hole mass and galaxy mass. Why they also use the word "grew"? In the dictionary it is stated: "undergo natural development by increasing in size and changing physically (of a living thing)" Galaxy is not a living thing. So why grew? Why not: increase, enlarge or become great. The verb grow is commonly used for all sorts of things. Cities grow. Savings grow. Industries grow. http://www.merriam-webster.com/dictionary/grow Link to comment Share on other sites More sharing options...
Ophiolite Posted January 2, 2016 Share Posted January 2, 2016 (edited) Why they also use the word "grew"? In the dictionary it is stated: "undergo natural development by increasing in size and changing physically (of a living thing)" Exports grew last year by 4.3% There is a growing expectation that extreme weather conditions will become more common. The growth of the Himalayas began when the Indian subcontinent collided with Asia. Grow is not exclusively used for living things. Edit: Cross posted with Strange. Edited January 2, 2016 by Ophiolite Link to comment Share on other sites More sharing options...
MigL Posted January 2, 2016 Share Posted January 2, 2016 Galaxies don't really 'grow'. Their mass is pretty constant as intergalactic space is very empty. Their present mass after 13.7 bill yrs is the result of gravitational accumulation of hydrogen/helium about quantum fluctuations in the primordial particle soup after the inflationary period ( yes, it was that homogenous ). Over the 13.7 bill yrs the hydrogen/helium has accumulated into stars, which have created heavier element dust, and so the number of stars in the galactic system may grow. Over that same period of time, at the center of the accumulation, the first giant ble stars formed, went supernova and created black holes. The 'shock waves' in the gas also spurred other star creation further out, and so on, and so on. Because of the high densities at the center of the accumulation, some of the resultant black holes would expand/merge over time creating the large central black hole. Once regular orbits had been established about this central gravitating mass, it would cease to be active and become dormant. This is the presnt day situation. Link to comment Share on other sites More sharing options...
Airbrush Posted January 3, 2016 Share Posted January 3, 2016 (edited) It's looks to me that significant amount of the stellar mass had been ejected to space. It looks like a significant amount of stellar mass has been ejected, but most of that returns to collide with the other galaxy again. Have you seen those computer simulations of collisions between galaxies? When galaxies collide some stars may be thrown away into the voids to never return to any galaxy. But most will come back in elliptical orbits to settle into an eliptical galaxy. Given enough time, every cluster of galaxies will end up in one giant eliptical galaxy. Even every supercluster will end up as one giant galaxy. They are gravitationally bound forever. Only superclusters are flying away from all other superclusters. The SBHs from the colliding galaxies will begin orbiting each other and the friction of the matter near the center will cause the heavy-weights to spiral into each other. That is unavoidable. Edited January 3, 2016 by Airbrush Link to comment Share on other sites More sharing options...
michel123456 Posted January 3, 2016 Share Posted January 3, 2016 (edited) Here is a simple experiment. Fill a tub with water, add some semi buoyant particles. Then take a blender to the center of the water and allow the impeller to spin for a while. Eventually you will get spiral waves as the water and particulates swirl The impeller represents the mass of the bulge including the BH. The BH contribution isnt due to the spin of the BH, but rather nearby stars and dust orbitting the BH inducing drag radially outward. Yes. Some time ago I made this experiment in a casserole not exactly with buoyant particles, but with boiled small leaves of salad that have almost the same density with water (they are floating freely everywhere in the liquid). The interesting phenomenon begins when you let the buoyant particles go round and round without the blender. They decelerate and they gather to the center. The tea leaf paradox https://en.wikipedia.org/wiki/Tea_leaf_paradox Edited January 3, 2016 by michel123456 Link to comment Share on other sites More sharing options...
David Levy Posted January 4, 2016 Author Share Posted January 4, 2016 (edited) It looks like a significant amount of stellar mass has been ejected, but most of that returns to collide with the other galaxy again. Have you seen those computer simulations of collisions between galaxies? When galaxies collide some stars may be thrown away into the voids to never return to any galaxy. But most will come back in elliptical orbits to settle into an eliptical galaxy. Given enough time, every cluster of galaxies will end up in one giant eliptical galaxy. Even every supercluster will end up as one giant galaxy. They are gravitationally bound forever. Only superclusters are flying away from all other superclusters. The SBHs from the colliding galaxies will begin orbiting each other and the friction of the matter near the center will cause the heavy-weights to spiral into each other. That is unavoidable. 1. You claim: "It looks like a significant amount of stellar mass has been ejected, but most of that returns to collide with the other galaxy again." Let's agree that this is correct by 100%. So, most of the mass returns to collide with the other galaxy. However, we also know that 50% of the stars are located outside the galaxies. The main answer for that was (as expected) - Galaxy collision. So, how could it be that that we are using the same phenomenon as an explanation to a very contradicted evidences? (Whenever we want to show that "the most massive galaxies in the universe and the suppermassive black holes at their hearts grew together over time",- we offer Galaxy-collision and prove that most of the stars stay at the galaxy, and in the same token, whenever it is important for us to show that "At least 50% of the stars are located outside the galaxies" - we also offer Galaxy-collision and prove that most of the stars are ejected away from the galaxy...) 2. In our universe there are billions of spiral galaxies. How many collisions we can see? Is it 0.01 of the total spiral galaxies? 0.001? or less then 0.00000001? Actually, if we also consider the effect of the expansion, Don't you think that the collision ratio should be very low? 3. Please also focus on the description – "…grew together OVER TIME" So it's not that just one collision per galaxy could be good enough. If they need to grew OVER TIME, we need to set many collisions per galaxy. Again and again and again - "over time". If the colisions are so rare, how could it be feasible? 4. Spiral shape – Is it correct that after collision, spiral galaxy should looks like elliptical galaxy? If so, do you agree that there is no way for spiral galaxy to increase its size by collision? Edited January 4, 2016 by David Levy Link to comment Share on other sites More sharing options...
Strange Posted January 4, 2016 Share Posted January 4, 2016 2. In our universe there are billions of spiral galaxies. How many collisions we can see? Is it 0.01 of the total spiral galaxies? 0.001? or less then 0.00000001?[/size][/font] They seem to be pretty common: http://hubblesite.org/newscenter/archive/releases/2011/30/full/ Remember that elliptical galaxies are the result of collions and make up about 10% of the galaxies we see. So your guess is several orders of magnitude out. Actually, if we also consider the effect of the expansion, Don't you think that the collision ratio should be very low? Expansion isn't relevant because it doesn't happen in galaxy clusters. Link to comment Share on other sites More sharing options...
David Levy Posted January 6, 2016 Author Share Posted January 6, 2016 (edited) Remember that elliptical galaxies are the result of collions and make up about 10% of the galaxies we see. So your guess is several orders of magnitude out. What about the other 90% of galaxies? For example - Spiral galaxies It is clear that collision should destroy the shape of spiral galaxy. Therefore, merged by collision is not even an option for for this type of galaxy. How the science explain the growing of spiral galaxy? They seem to be pretty common: http://hubblesite.org/newscenter/archive/releases/2011/30/full/ What about the black holes merged? In this articale They do not even try to verify this critical issue. How can they discuss about large galaxies merged without understanding if black holes merged is feasible? This is the most critical issue! Why they do not try to simulate this merging process? Without a real proof for black holes merged there is no meaning for any further discussion on gaining mass due to collision/merge. Anyhow, let's see if it is pretty common: It is stated: "Having an accurate value for the merger rate is critical because galactic collisions may be a key process that drives galaxy assembly, rapid star formation at early times, and the accretion of gas onto central supermassive black holes at the centers of galaxies," Lotz explains. Never the less, in the same token it is stated "Large galaxies merged with each other on average once over the past 9 billion years". So, large galaxies merge with each other only once 9 Billion years. It's about 1.35 times from day one of the Universe. With regards to the small galaxies it is three times more often than the large galaxies: So it is: 3 x 1.35 = 4 times. So, at this low rate of collisions how could it be used as an answer for the galaxy assembly? Till now, I have no idea what is the real rate of galaxies collision. Why it is not stated clearly? Instead of giving a direct answer, they use the example of car crash. "These different techniques probe mergers at different 'snapshots' in time along the merger process," Lotz says. "It is a little bit like trying to count car crashes by taking snapshots. If you look for cars on a collision course, you will only see a few of them. If you count up the number of wrecked cars you see afterwards, you will see many more. Studies that looked for close pairs of galaxies that appeared ready to collide gave much lower numbers of mergers than those that searched for galaxies with disturbed shapes, evidence that they're in smashups."" So, they admit that the crashes are very rare, but they think that they have an idea how to overcome. Therefore, let me ask again - Please let me know the current snapshot of the galaxies collisions percentage. Edited January 6, 2016 by David Levy Link to comment Share on other sites More sharing options...
Strange Posted January 6, 2016 Share Posted January 6, 2016 What about the black holes merged? In this articale They do not even try to verify this critical issue. How can they discuss about large galaxies merged without understanding if black holes merged is feasible? This is the most critical issue! Why they do not try to simulate this merging process? Your repeated expressions of disbelief based on your profound (and, I suspect, wilful) ignorance is becoming very tedious. Why don't you go and study these things before making such asinine posts and making a fool of yourself. A large amount of work has been done on black hole mergers. It is a fascinating subject. There are even simulations of how they would behave, particularly interesting in the last few moments and the following oscillations ("ring down"). There are also several projects ongoing to detect the direct evidence of such mergers. I am not going to waste my time searching for relevant articles and papers because all you will do is read the tile, misunderstand it and then ask more questions trying to push your personal agenda, which is purely based on your ignorance of the subject. In the unlikely event you want to learn something about this, there are some keywords in the above you can use. Link to comment Share on other sites More sharing options...
Ophiolite Posted January 6, 2016 Share Posted January 6, 2016 Therefore, let me ask again - Please let me know the current snapshot of the galaxies collisions percentage. 1. I am sure you are aware that science does not have all the answers. That, indeed, is why science exists: to develop more answers. 2. You seem to imply that there is something negative about as not having an accurate number. Do you have negative feelings about this and if so why? 3. You are aware, that if reasonable numbers exist, you could find these out by judicious literature searches. Yes? Have you done so? If not, why not? Link to comment Share on other sites More sharing options...
Strange Posted January 6, 2016 Share Posted January 6, 2016 (edited) By chance, I came across this: Composite image shows two black holes orbiting each other - phys.org Edited January 6, 2016 by Strange Link to comment Share on other sites More sharing options...
David Levy Posted January 7, 2016 Author Share Posted January 7, 2016 (edited) Your repeated expressions of disbelief based on your profound (and, I suspect, wilful) ignorance is becoming very tedious. Why don't you go and study these things before making such asinine posts and making a fool of yourself. A large amount of work has been done on black hole mergers. It is a fascinating subject. There are even simulations of how they would behave, particularly interesting in the last few moments and the following oscillations ("ring down"). Dear Strange I'm sorry for asking too difficult questions. You do not waste your time for nothing. I do remember your valuable answers and I do appreciate all your effort. For example - With regards to the black hole, you have already claimed: So what is unknown is how black holes can grow to be so massive. But it doesn't seem to be very relevant to the formation of galaxies. Therefore, I have used your statement that it is unknown how black holes can grow to be so massive. Actually, I didn't find even one article which can offer any real solution for that process. With all the respect, simulation can't be the only replacement for our willing for real evidence. Somehow, it seems that the science set the target and now they just need to place the arrow on the spot. You claim: There are also several projects ongoing to detect the direct evidence of such mergers. Why they do not try to find if that process is feasible? Why they put so much activity in order to detect direct evidence of such mergers? Why they do not try to find some other solutions? The science is using an example of car crashes in order to highlight the merging process of galaxies - So let me ask the following: Is it feasible that a crash between two cars can create a new truck? Sorry, but so far I didn't get a real answer if two smalls galaxies with two small black holes can set a bigger galaxy with merged black hole and merged stars. And so far we all know that collision can't be an answer for massive spiral galaxy growing activity. There are many other open issues with regards to that collision/merging process. However, as I do not want to upset you, I will not ask you any more questions about collisions. (Never the less, more questions to come on other aspects of this tread...) By chance, I came across this: Composite image shows two black holes orbiting each other - phys.org Thanks Great article. However, we would expect that each supper massive black hole had been in the past is a core of some type of galaxy. What we see is just a left over from the galaxies mass. So where is all the mass of the galaxies? Therefore, even if we get a merged black hole due to collision, it confirms that most of the galaxies mass is ejected into space in that process. Edited January 7, 2016 by David Levy Link to comment Share on other sites More sharing options...
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