'13-07-27, 13:51 DeiRenDopa	Originally Posted by Charles Chandler Oh, please. I'm agreeing with the scientists who have calculated and concluded that the Pannekoek-Rosseland effect is a weak force. You agree as well. But you can still figure out how to make an insult out of the fact that I haven't proven it to you? You're the one who brought it up — you prove it! But I'm not going to waste my time with your argumentativeness anymore. If you ask a relevant question, without 9/10 of it being emotional baggage, I answer it to the best of my ability. Otherwise, I'll ignore it. Call me whatever you want, but I don't have time for arguments that were manufactured just for the sake of arguing. Let's try some simple fact checking then. DD: Yeah, the sun which has a hot internal core should follow ideal gas law: no CC: Then you disagree with Jørgen Christensen-Dalsgaard, author of the standard model. What is CC referring to? Well, the caption to Figure 3 on one of his webpages reads, in part "The density gradient of the Sun in the Dalsgaard model", with "Dalsgaard" being a link. Click it, and you get a table, the first line of which is "sound speed, etc for Model S (Christensen-Dalsgaard et al. 1996)" Fair enough, so CC has read "Christensen-Dalsgaard et al. 1996" and extracted (downloaded) the relevant data, right? Maybe not CC gives us a (full?) list of his references, in this post. Strangely, Christensen-Dalsgaard et al. 1996 is not among them. If CC has not - apparently (please confirm CC) - actually read that 1996 paper, how did he come to conclude that "Model S" is the standard model? More interestingly, perhaps, how did he conclude that the "Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws"? On Prof. Jørgen Christensen-Dalsgaard's (JC-D) own (Aarhus University) website, near the bottom under "Some potentially interesting material:", there is "Reference solar model. This is Model S of Christensen-Dalsgaard et al. (1996) which has been used fairly extensively as reference in helioseismic inversion." Click the link and you read the following short introductory para: Originally Posted by Jørgen Christensen-Dalsgaard The model provided here has been used fairly extensively as a reference for helioseismic inversion. It is commonly known as Model S, and described by Christensen-Dalsgaard et al. (1996). Briefly, the model uses OPAL equation of state and opacity, and includes settling of helium and heavy elements. Hmm, no mention of "only acknowledges the ideal gas laws"! So, to sum up: 1) it seems that CC has not read the 1996 JC-D et al. paper, and 2) JC-D's own website (the closest thing to an official source) makes no mention of using only the ideal gas laws. Of course, as even a casual skim of any standard solar physics textbook would tell you, there is no single ("the") standard model. You can also realize this by looking at the references in the 1996 JC-D et al. paper, and the papers (etc) which cite it. An example is "A Comparison of Precise Solar Models with Simplified Physics", a 1995 conference presentation which has JC-D as an author. You will also very quickly realize that CC's "only acknowledges the ideal gas laws" is a figment of his imagination. I'll let ben m close this post: Originally Posted by ben m Seriously, this is the Nth time that your "solar model" is motivated by apparently unresearched guesswork about things that are wrong with mainstream models. Due to your lack of research, you're not making statements about what's wrong with mainstream solar models. You're making statements about what's wrong with your guesses as to what might be in a mainstream solar model.
'13-07-27, 14:19 ben m	Originally Posted by Charles Chandler OK, then what IS the field source? The field source is currents, as usual. The currents are generated by induction (Faraday's law, i.e. changing B fields) not by electrostatics, and are amplified by advection (rotation/flow/turbulence etc.). The idea is that an infinitesimally small seed B field generates a small current, the current is dragged along with some fluid motion which increases its amplitude; the amplified current generates a larger B field; lather, rinse, repeat. The growth can be exponential, which means that the seed field may be as small as a random statistical fluctuation.
'13-07-27, 16:04 Charles Chandler	Originally Posted by DeiRenDopa Fair enough, so CC has read "Christensen-Dalsgaard et al. 1996" and extracted (downloaded) the relevant data, right? Maybe not CC gives us a (full?) list of his references, in this post. Strangely, Christensen-Dalsgaard et al. 1996 is not among them. If CC has not - apparently (please confirm CC) - actually read that 1996 paper, how did he come to conclude that "Model S" is the standard model? More interestingly, perhaps, how did he conclude that the "Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws"? Here is a quote from the 1996 paper (with my bolding). Originally Posted by Dalsgaard et al., 1996, pg. 2 The structure of a star is a result of a balance of forces, a balance between the energy loss at the stellar surface and energy generation in the core, and stationary energy transport between the core and the surface. The balance of forces, described as hydrostatic equilibrium, provides a relation between the pressure gradient and the gravitational acceleration. The force of gravity is determined by the density distribution in the star: thus we must relate density to pressure, through the properties of the matter and hence the microphysics. More specifically, the relevant properties of stellar matter are expressed by the equation of state, connecting pressure, density, temperature, and composition. The latter is often characterized by the fractional mass abundances of hydrogen, helium and heavier elements. So where did I get the idea that the density gradient is estimated on the basis of the ideal gas laws? Anyway, the authors go on to acknowledge other factors... Originally Posted by Dalsgaard et al., 1996, pg. 7 The simplest model is that of a mixture of fully ionized nuclei and electrons obeying the perfect gas law. However, an ideal equation of state can be more general by including deviations from the perfect gas law, due to ionization, radiation and degenerate electrons. Departures from ideality arise from dynamical interactions between the components of the plasma. One measure of the nonideality is the ratio between the average potential energy resulting from the Coulomb interaction and the kinetic energy of particles. Although the solar plasma is only slightly nonideal, the deviations from nonideality can be studied in detail because of the observational constraints afforded by helioseismology. After stating that the solar plasma is only slightly nonideal, and the deviation is really only useful in tracking down certain helioseismic anomalies, they then describe the actual nature of the nonideal conditions. Most of that part I agree with, including acknowledgement of pressure ionization. But since the authors think that the plasma is only slightly nonideal, they believe that there's no need to include such factors in the density calculations. Originally Posted by ben m The field source is currents, as usual. The currents are generated by induction (Faraday's law, i.e. changing B fields) not by electrostatics, and are amplified by advection (rotation/flow/turbulence etc.). The idea is that an infinitesimally small seed B field generates a small current, the current is dragged along with some fluid motion which increases its amplitude; the amplified current generates a larger B field; lather, rinse, repeat. The growth can be exponential, which means that the seed field may be as small as a random statistical fluctuation. Runaway B fields — why didn't I think of that? So what prevents them from getting strong? The solar dynamo field is only 1 Gauss — only twice the strength of the Earth's average field, despite the Sun being 333,000 times more massive. The excellent conductivity of the solar plasma shouldn't offer any measurable resistance to these runaway currents and attendant magnetic fields.
'13-07-27, 18:30 ben m	Originally Posted by Charles Chandler After stating that the solar plasma is only slightly nonideal, and the deviation is really only useful in tracking down certain helioseismic anomalies, they then describe the actual nature of the nonideal conditions. Most of that part I agree with, including acknowledgement of pressure ionization. But since the authors think that the plasma is only slightly nonideal, they believe that there's no need to include such factors in the density calculations. Geez. So you acknowledge that the authors are not somehow blindly devoted to the ideal gas law---they take non-ideal conditions seriously. You acknowledge that the authors are aware of particle-particle interactions. You simply deny that their answer can be correct, because you can't make it work with your intuition for fluids. Sorry to use the C-word, but that is straight-up crackpot reasoning. Wilfred Hodges points it out in his classic "An Editor Recalls Some Hopeless Papers" Originally Posted by http://www.math.ucla.edu/~asl/bsl/0401/0401-001.ps How does anybody get into a state of mind where they persuade themselves that you can criticise an argument by suggesting a different argument which doesn’t reach the same conclusion? When an amateur/intuitive calculation disagrees with a detailed professional calculation, it generally means that the amateur is wrong. Recall that I said, based on my graduate-level coursework in thermodynamics, that I expected the Coulomb force to have a minimal effect on the plasma equation of state. You found a detailed calculation, by someone who takes plasma equation of state very seriously, whose result is that the Coulomb force has a minimal effect on the plasma equation of state. How much clearer an answer can you ask for? The Coulomb force does not do what you guessed it will do. Quote: Runaway B fields — why didn't I think of that? So what prevents them from getting strong? The solar dynamo field is only 1 Gauss — only twice the strength of the Earth's average field, despite the Sun being 333,000 times more massive. The excellent conductivity of the solar plasma shouldn't offer any measurable resistance to these runaway currents and attendant magnetic fields. It's a complex system; nonzero resistivity is present, and actually necessary, for dynamo action to take effect. It's a complex, sometimes chaotic system, and your attempt to invent scaling laws off the top of your head might reasonably be expected not to work.
'13-07-27, 20:51 Charles Chandler	Originally Posted by ben m Geez. So you acknowledge that the authors are not somehow blindly devoted to the ideal gas law---they take non-ideal conditions seriously. You acknowledge that the authors are aware of particle-particle interactions. You simply deny that their answer can be correct, because you can't make it work with your intuition for fluids. I don't think that it's just my intuition for fluids. From post #155: Originally Posted by Charles Chandler I still stand by my assertion that the solar density gradient is non-Newtonian. The supersonic hydrodynamics of photospheric granules, and the occasional post-flare s-waves, cannot be rationalized within any Newtonian regime. There shouldn't be a boundary there, much less one with supersonic flows. Scientists invoke MHD, but without identifying the magnetomotive forces, which can only be electric currents, much less the electromotive forces, where the resting potentials necessary to drive such currents shouldn't be possible in an excellent conductor. So there are many unanswered questions, and I'm seeking physical answers. And I'll continue until I see the issues directly addressed. Maybe scientists who invoke MHD to describe the supersonic flows in the photosphere are crackpots, because they don't know that non-Newtonian forces have already been considered, and dismissed, by other scientists. Be sure to let them know. Then, you picked up on my use of the term "resting potentials", and cited work on dynamo theories, as evidence that electric currents do not need E fields. The last part is true, though whether or not currents and magnetic fields can form into a positive feedback loop isn't quite as universally accepted as you're trying to make it sound. I could question you further on that, but I'd like to get back to the central point of this thread. Are you saying that dynamo-generated B fields are responsible for the supersonic hydrodynamic behaviors of the Sun's surface?
'13-07-27, 23:11 ben m	Originally Posted by Charles Chandler Are you saying that dynamo-generated B fields are responsible for the supersonic hydrodynamic behaviors of the Sun's surface? There is a phenomenon in creationist arguments called the "Gish gallop". The creationist will make a crazy claim based on 10 seconds of confabulation; a scientist refutes it based on 1 hour of research and reading; the creationist ignores the refutation, and makes an new crazy claim. Repeat until the scientist runs out of patience. A scientific audience hears this as "wow, the creationist made 10 obviously-wrong statements in a row, then one statement about a fossil I've never even heard of, then 19 more whoppers. We could spend all day just on the wrongness of claim #1 but he moved on so fast." The creationist audience registers this as "Claim 11 stumped the scientist! Creationism wins the debate!" Your Web page makes a bunch of claims that I happen to know to be wrong, and for which I have the contradictory details ready off the top of my head. Those include: the EOS of a hot plasma, some aspects of plasma opacity (although others here have this covered better than I do), whether your charge-layering can be an energy source, and various claims about fusion, various claims about dynamos. In other words, we could spend all day explaining why plasma is actually expected to be compressible. This seems to be important to your model, and is worth spending that time on. I'm not going to follow a "Gish gallop" into some detailed MHD question about solar granules, nor into a "controversy" about dynamo action. (I'm not well-enough-informed on those details to comment further without hours of reading.) Given that you appear to have just learned about dynamos in this very thread, and to have leapt straight into inventing new 30-seconds-of-thought misconceptions about them and using those misconceptions to deny that dynamo action work ... why should I expect you to be making well-informed claims about the state of the field? I don't. I think there's enough in this thread to prove that your entire picture is gibberish. The refutations you've already seen are the sort of thing that, if you were a scientist, would send you back to the drawing board. Instead, they appear to have sent you into a Gish gallop. Ugh.
'13-07-27, 23:43 Charles Chandler	Originally Posted by ben m The refutations you've already seen are the sort of thing that, if you were a scientist, would send you back to the drawing board. Instead, they appear to have sent you into a Gish gallop. Ugh. Ummm, trying to get the discussion back to the OP (at least for the thread that I started, which was merged into this one, and which is post #14 in this thread) isn't exacting "Gish galloping". I'm maintaining that the observable evidence on the Sun's surface is proof of a non-Newtonian density gradient. Nobody seems capable of addressing this issue head-on, but it's where I started, and it's what I keep going back to. There are many implications to this, and we've explored the periphery of the domain. But I'm not the one who is wandering. Nice try though. Can anyone refute the claim that the observations of supersonic hydrodynamic flows on the surface of the Sun are proof of non-Newtonian density gradient? It was suggested that the density gradient is purely Newtonian, but that the opacity gives the illusion of a distinct surface. I guess that this could be extended to the contention that the "supersonic flows" in the granules are just illusions, while the plasma is actually stationary. Or the plasma might be moving in convective currents, well below the speed of sound, but in or around such flows are illusions of far faster flows, or something. This would be contrary to the mainstream view, that the plasma is actually supersonic. But then supersonic convective currents are a contradiction in terms, and such "convection" is modeled with MHD, not traditional fluid dynamics. So I call that just a bunch of ad hoc heuristics, and I'm asking about the physical forces. I doubt that I'll get an answer, because in the mainstream, there isn't one. But it was still worth asking.
'13-07-28, 04:17 sol invictus	Originally Posted by Charles Chandler Can anyone refute the claim that the observations of supersonic hydrodynamic flows on the surface of the Sun are proof of non-Newtonian density gradient? It was suggested that the density gradient is purely Newtonian, but that the opacity gives the illusion of a distinct surface. I guess that this could be extended to the contention that the "supersonic flows" in the granules are just illusions, while the plasma is actually stationary. Or the plasma might be moving in convective currents, well below the speed of sound, but in or around such flows are illusions of far faster flows, or something. This would be contrary to the mainstream view, that the plasma is actually supersonic. But then supersonic convective currents are a contradiction in terms, and such "convection" is modeled with MHD, not traditional fluid dynamics. So I call that just a bunch of ad hoc heuristics, and I'm asking about the physical forces. I doubt that I'll get an answer, because in the mainstream, there isn't one. But it was still worth asking. http://iopscience.iop.org/0004-637X/..._284.text.html Quote: Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ∼3%-4% of the solar surface at any time... a process that has been studied in detail by means of two- and three-dimensional simulations (e.g., Stein & Nordlund 1989, 1998; Cattaneo et al. 1990; Steffen & Freytag 1991; Steiner et al. 1998; Gadun et al. 1999; Ploner et al. 1999).
'13-07-28, 06:53 DeiRenDopa	Originally Posted by Charles Chandler Originally Posted by me Fair enough, so CC has read "Christensen-Dalsgaard et al. 1996" and extracted (downloaded) the relevant data, right? Maybe not CC gives us a (full?) list of his references, in this post. Strangely, Christensen-Dalsgaard et al. 1996 is not among them. If CC has not - apparently (please confirm CC) - actually read that 1996 paper, how did he come to conclude that "Model S" is the standard model? More interestingly, perhaps, how did he conclude that the "Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws"? Here is a quote from the 1996 paper (with my bolding). "The 1996 paper" is "The Current State of Solar Modeling", by J. Christensen-Dalsgaard, W. Däppen, S. V. Ajukov, E. R. Anderson, H. M. Antia, S. Basu, V. A. Baturin, G. Berthomieu, B. Chaboyer, S. M. Chitre, A. N. Cox, P. Demarque, J. Donatowicz, W. A. Dziembowski, M. Gabriel, D. O. Gough, D. B. Guenther, J. A. Guzik, J. W. Harvey, F. Hill, G. Houdek, C. A. Iglesias, A. G. Kosovichev, J. W. Leibacher, P. Morel, C. R. Proffitt, J. Provost, J. Reiter, E. J. Rhodes Jr., F. J. Rogers, I. W. Roxburgh, M. J. Thompson, R. K. Ulrich. Here is the abstract: Originally Posted by J. Christensen-Dalsgaard et al. Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations. Here is the Science webpage from which I copied the abstract; at the top it says: "Science 31 May 1996: Vol. 272 no. 5266 pp. 1286-1292 DOI: 10.1126/science.272.5266.1286" If you click on the link "Full Text (PDF)", you learn that a) you can join/subscribe, b) purchase the article, c) activate your membership. Those JREF members with appropriate institutional access can get this (are you one of those, CC?) paper for free, as can AAAS members and Science subscribers (are you one of those, CC?); the rest of us must pay. Quote: Originally Posted by Dalsgaard et al., 1996, pg. 2 The structure of a star is a result of a balance of forces, a balance between the energy loss at the stellar surface and energy generation in the core, and stationary energy transport between the core and the surface. The balance of forces, described as hydrostatic equilibrium, provides a relation between the pressure gradient and the gravitational acceleration. The force of gravity is determined by the density distribution in the star: thus we must relate density to pressure, through the properties of the matter and hence the microphysics. More specifically, the relevant properties of stellar matter are expressed by the equation of state, connecting pressure, density, temperature, and composition. The latter is often characterized by the fractional mass abundances of hydrogen, helium and heavier elements. So where did I get the idea that the density gradient is estimated on the basis of the ideal gas laws? And...? Where did you get that (false) idea? Had you read this paper before you first posted here? (if so, why did you not list it earlier? why was it not referenced on your webpage?) Quote: Anyway, the authors go on to acknowledge other factors... Originally Posted by Dalsgaard et al., 1996, pg. 7 The simplest model is that of a mixture of fully ionized nuclei and electrons obeying the perfect gas law. However, an ideal equation of state can be more general by including deviations from the perfect gas law, due to ionization, radiation and degenerate electrons. Departures from ideality arise from dynamical interactions between the components of the plasma. One measure of the nonideality is the ratio between the average potential energy resulting from the Coulomb interaction and the kinetic energy of particles. Although the solar plasma is only slightly nonideal, the deviations from nonideality can be studied in detail because of the observational constraints afforded by helioseismology. After stating that the solar plasma is only slightly nonideal, and the deviation is really only useful in tracking down certain helioseismic anomalies, they then describe the actual nature of the nonideal conditions. Most of that part I agree with, including acknowledgement of pressure ionization. But since the authors think that the plasma is only slightly nonideal, they believe that there's no need to include such factors in the density calculations. If someone has a link to a full text version (preferably PDF) of the paper, would you please post it? Why? Why am I asking this? Because I'd like every reader of this thread to have the opportunity to do their own fact checking. In particular, I'd like us all to see the extent to which what CC has posted can be shown to be, um, somewhat economical with the truth. In making that assessment, let us not forget how CC introduced this model (and, by implication, this paper) to us, here in this thread: Then you disagree with Jørgen Christensen-Dalsgaard, author of the standard model. That's OK — so do I. (source) The Dalsgaard model doesn't take the Coulomb barrier into account, which means that the density due just to the force of gravity is grossly overestimated. (source) Such people have yet to inform Jørgen Christensen-Dalsgaard, author of the standard model, who still uses just the ideal gas laws. (source) the standard model of the Sun's density gradient (i.e., the Dalsgaard model) is the ideal gas law plus gravity. (in response to sol's question "You seem to think the standard solar model is the ideal gas law plus gravity. Is that right?", (source) The Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws (source)
'13-07-28, 07:22 DeiRenDopa	Originally Posted by Charles Chandler Originally Posted by ben m The refutations you've already seen are the sort of thing that, if you were a scientist, would send you back to the drawing board. Instead, they appear to have sent you into a Gish gallop. Ugh. Ummm, trying to get the discussion back to the OP (at least for the thread that I started, which was merged into this one, and which is post #14 in this thread) isn't exacting "Gish galloping". I'm maintaining that the observable evidence on the Sun's surface is proof of a non-Newtonian density gradient. Nobody seems capable of addressing this issue head-on, but it's where I started, and it's what I keep going back to. There are many implications to this, and we've explored the periphery of the domain. But I'm not the one who is wandering. Nice try though. Time for some more fact checking perhaps? Post #14 begins (sans link) "Here is an introduction to the solar model that I'm developing, posted here to encourage critical reviews." It then goes on to say that "the standard model of the Sun fails to explain even the simplest of solar observations", the very first of which cited is the apparent sharp limb of the Sun, when imaged in a narrow band centered on Balmer H-alpha. The two next posts - #15 and #16 - point out (albeit in a rather blunt fashion) that you seem to be rather ignorant of standard solar models. Your response? It's in post #25, and shows (to me anyway) that you clearly had not, at that time, actually read the Christensen-Dalsgaard et al. 1996 paper (or at least not understood it). Ironically, you even said "Temperature "could" cause such a threshold (sort of, at least)" (referring to "some sort of threshold is being crossed"). edd tried, in his usual gentle way, to suggest that this is something you really, really should look into. That particular thread of back-and-forth goes on for some time (I encourage readers to review at their leisure). I came away with my initial impressions amply confirmed; as is so often the case, I see that ben m succinctly summarized what I was thinking: " as to what might be in a mainstream solar model.your guesses about things that are wrong with mainstream models. Due to your lack of research, you're not making statements about what's wrong with mainstream solar models. You're making statements about what's wrong with apparently unresearched guessworkSeriously, this is the Nth time that your "solar model" is motivated by " Quote: Can anyone refute the claim that the observations of supersonic hydrodynamic flows on the surface of the Sun are proof of non-Newtonian density gradient? It was suggested that the density gradient is purely Newtonian, but that the opacity gives the illusion of a distinct surface. I guess that this could be extended to the contention that the "supersonic flows" in the granules are just illusions, while the plasma is actually stationary. Or the plasma might be moving in convective currents, well below the speed of sound, but in or around such flows are illusions of far faster flows, or something. This would be contrary to the mainstream view, that the plasma is actually supersonic. But then supersonic convective currents are a contradiction in terms, and such "convection" is modeled with MHD, not traditional fluid dynamics. If you still don't - apparently - have a clue as to what the standard textbook explanation is for the apparently sharp limb on the Sun (when viewed in certain wavelengths), I seriously doubt you'd understand much of any explanation of these phenomena. So why not try to understand something simple first? For example, why not get hold of a standard textbook and start reading? Quote: So I call that just a bunch of ad hoc heuristics, and I'm asking about the physical forces. I doubt that I'll get an answer, because in the mainstream, there isn't one. But it was still worth asking. So, with your PhD in helioseismology, followed by ten years' work on granular convection, you, CC, are most definitely in a position to say there's no mainstream answer. Right, got it.
'13-07-28, 08:16 ben m	Originally Posted by Charles Chandler such "convection" is modeled with MHD, not traditional fluid dynamics. So I call that just a bunch of ad hoc heuristics, and I'm asking about the physical forces. Traditional fluid dynamics doesn't work on magetized conductors. Using it is not ad hoc, it's correct. "Traditional fluid mechanics" is MHD with all magnetic forces set to zero. Why would you do that?
'13-07-28, 09:57 Charles Chandler	Originally Posted by L. R. Bellot Rubio (2009) Hydrodynamic simulations of granular convection predict the existence of supersonic flows covering ∼3%-4% of the solar surface at any time... a process that has been studied in detail by means of two- and three-dimensional simulations (e.g., Stein & Nordlund 1989, 1998; Cattaneo et al. 1990; Steffen & Freytag 1991; Steiner et al. 1998; Gadun et al. 1999; Ploner et al. 1999). I'm not questioning whether or not supersonic flows can be "simulated". I'm questioning whether or not the "simulations" took into account that by the laws of fluid dynamics, the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. Originally Posted by DeiRenDopa If someone has a link to a full text version (preferably PDF) of the paper, would you please post it? http://quake.stanford.edu/~sasha/PAPERS/models.pdf Originally Posted by DeiRenDopa Why am I asking this? Because I'd like every reader of this thread to have the opportunity to do their own fact checking. In particular, I'd like us all to see the extent to which what CC has posted can be shown to be, um, somewhat economical with the truth. In making that assessment, let us not forget how CC introduced this model (and, by implication, this paper) to us, here in this thread: Then you disagree with Jørgen Christensen-Dalsgaard, author of the standard model. That's OK — so do I. (source) The Dalsgaard model doesn't take the Coulomb barrier into account, which means that the density due just to the force of gravity is grossly overestimated. (source) Such people have yet to inform Jørgen Christensen-Dalsgaard, author of the standard model, who still uses just the ideal gas laws. (source) the standard model of the Sun's density gradient (i.e., the Dalsgaard model) is the ideal gas law plus gravity. (in response to sol's question "You seem to think the standard solar model is the ideal gas law plus gravity. Is that right?", (source) The Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws (source) Ummm, yes, I have said repeatedly that the Dalsgaard model only takes the ideal gas laws into account. To be slightly more accurate, I quoted from the original paper (with my bolding): Originally Posted by Dalsgaard et al., 1996, pg. 7 Although the solar plasma is only slightly nonideal, the deviations from nonideality can be studied in detail because of the observational constraints afforded by helioseismology. In essence, Dalsgaard is saying that the only significance of the nonideality is that it can be used to track down some of the wave transmission speed anomalies. Originally Posted by ben m Traditional fluid dynamics doesn't work on magnetized conductors. Using it is not ad hoc, it's correct. "Traditional fluid mechanics" is MHD with all magnetic forces set to zero. Why would you do that? I'll tell you why. The average magnetic field is only 1 Gauss (which isn't much), but more tellingly, the behaviors of the granules are the same, regardless of the polarity and strength of the magnetic fields. This would tend to mean that the magnetic force isn't a factor, don't you think?
'13-07-28, 09:57 DeiRenDopa	Originally Posted by ben m Originally Posted by Charles Chandler After stating that the solar plasma is only slightly nonideal, and the deviation is really only useful in tracking down certain helioseismic anomalies, they then describe the actual nature of the nonideal conditions. Most of that part I agree with, including acknowledgement of pressure ionization. But since the authors think that the plasma is only slightly nonideal, they believe that there's no need to include such factors in the density calculations. Geez. So you acknowledge that the authors are not somehow blindly devoted to the ideal gas law---they take non-ideal conditions seriously. You acknowledge that the authors are aware of particle-particle interactions. You simply deny that their answer can be correct, because you can't make it work with your intuition for fluids. I think there's rather more to it than that. There are various, um, patterns in CC's posting which suggest that he might be, um, somewhat disingenuous (others may chose to use a rather stronger word). As is clear for all to see, CC chose to call the "Model S" in J. Christensen-Dalsgaard et al. (1996) - "the 1996 paper", for short - the standard model. Why? In 1996 the solar neutrino problemWP was very much a hot topic, and a huge amount of work was being put into solar models. Model S is just one - of hundreds? - of such models published around that time. Fast forward a half decade or so, and that problem is resolved. However, work on solar models continued, and continues. One kind of solar model is called "the standard solar model"WP, and WP gives a "Christensen-Dalsgaard review of helioseismology" as a source. Is this the 1996 paper? Why no, it isn't! It's a 2003 one (link is to the arXiv preprint). I find it very hard to square CC's characterizations of "the mainstream view" of solar physics with what's in that 2003 paper. It gets even more interesting. Recall that CC is all hot and bothered about stuff that's happening at/near the top of the photosphere - razor sharp transitions, granular convection, supersonic flows, etc. And he has said, more than once, that the standard solar model cannot account for these phenomena (nor the observations which descriptions of these phenomena are based on). But is the standard solar model - in any form, with ideal gas laws or not - applicable for the study (and understanding) of such phenomena? Let's look at what WP says (the 2003 Christensen-Dalsgaard review of helioseismology contains more details, along with tons of references, if you're interested in digging deeper): Originally Posted by WP The standard solar model (SSM) is a mathematical treatment of the Sun as a spherical ball of gas (in varying states of ionisation, with the hydrogen in the deep interior being a completely ionised plasma). This model, technically the spherically symmetric quasi-static model of a star, has stellar structure described by several differential equations derived from basic physical principles. The model is constrained by boundary conditions, namely the luminosity, radius, age and composition of the Sun, which are well determined. Hmm, "spherically symmetric quasi-static" eh? May not be such a good model to use for convection in granules perhaps. Originally Posted by WP The SSM serves two purposes: it provides estimates for the helium abundance and mixing length parameter by forcing the stellar model to have the correct luminosity and radius at the Sun's age, it provides a way to evaluate more complex models with additional physics, such as rotation, magnetic fields and diffusion or improvements to the treatment of convection, such as modelling turbulence, and convective overshooting. Like the Standard Model of particle physics and the standard cosmology model the SSM changes over time in response to relevant new theoretical or experimental physics discoveries. Wowsers! Looks like the SSM is quite different to how CC characterized it! Reading on ... Originally Posted by WP Simulations of near-surface convection A more realistic description of the uppermost part of the convection zone is possible through detailed three-dimensional and time-dependent hydrodynamical simulations, taking into account radiative transfer in the atmosphere.[6] Such simulations successfully reproduce the observed surface structure of solar granulation,[7] as well as detailed profiles of lines in the solar radiative spectrum, without the use of parametrized models of turbulence.[8] The simulations only cover a very small fraction of the solar radius, and are evidently far too time-consuming to be included in general solar modeling. Extrapolation of an averaged simulation through the adiabatic part of the convection zone by means of a model based on the mixing-length description, demonstrated that the adiabat predicted by the simulation was essentially consistent with the depth of the solar convection zone as determined from helioseismology.[9] An extension of mixing-length theory, including effects of turbulent pressure and kinetic energy, based on numerical simulations of near-surface convection, has been developed Got that CC? Back to ben m: Quote: Sorry to use the C-word, but that is straight-up crackpot reasoning. [...] When an amateur/intuitive calculation disagrees with a detailed professional calculation, it generally means that the amateur is wrong. Recall that I said, based on my graduate-level coursework in thermodynamics, that I expected the Coulomb force to have a minimal effect on the plasma equation of state. You found a detailed calculation, by someone who takes plasma equation of state very seriously, whose result is that the Coulomb force has a minimal effect on the plasma equation of state. How much clearer an answer can you ask for? The Coulomb force does not do what you guessed it will do. In this case, CC - deliberately? - misrepresented the nature and scope of the SSM, so setting up a strawman. He then proceeded to viciously attack the strawman, and in the process imply that the scientists who worked on it were ignorant dolts (or worse). But perhaps I'm wrong. Perhaps it's all a huge misunderstanding on CC's part ...
'13-07-28, 10:22 DeiRenDopa	Originally Posted by Charles Chandler Originally Posted by me If someone has a link to a full text version (preferably PDF) of the paper, would you please post it? http://quake.stanford.edu/~sasha/PAPERS/models.pdf Quote: Why? Why am I asking this? Because I'd like every reader of this thread to have the opportunity to do their own fact checking. In particular, I'd like us all to see the extent to which what CC has posted can be shown to be, um, somewhat economical with the truth. In making that assessment, let us not forget how CC introduced this model (and, by implication, this paper) to us, here in this thread: Then you disagree with Jørgen Christensen-Dalsgaard, author of the standard model. That's OK — so do I. (source) The Dalsgaard model doesn't take the Coulomb barrier into account, which means that the density due just to the force of gravity is grossly overestimated. (source) Such people have yet to inform Jørgen Christensen-Dalsgaard, author of the standard model, who still uses just the ideal gas laws. (source) the standard model of the Sun's density gradient (i.e., the Dalsgaard model) is the ideal gas law plus gravity. (in response to sol's question "You seem to think the standard solar model is the ideal gas law plus gravity. Is that right?", (source) The Dalsgaard model gets the density right, but it only acknowledges the ideal gas laws (source) Ummm, yes, I have said repeatedly that the Dalsgaard model only takes the ideal gas laws into account. To be slightly more accurate, I quoted from the original paper (with my bolding): Originally Posted by Dalsgaard et al., 1996, pg. 7 Although the solar plasma is only slightly nonideal, the deviations from nonideality can be studied in detail because of the observational constraints afforded by helioseismology. In essence, Dalsgaard is saying that the only significance of the nonideality is that it can be used to track down some of the wave transmission speed anomalies. Yes, it is true (that you have repeatedly said that). Let's see what Model S actually incorporates, shall we? "In the following we use as reference a standard solar model, Model S, computed with the global parameters mentioned above (22)" - that's from page 5 of the PDF in the link you posted above (thanks). What is "(22)"? It's a footnote, which begins: "The model used the OPAL equation of state and opacities (34)" And "(34)" begins "For the OPAL opacity project," but we want the OPAL equation of state; here's what (34) says "Furthermore, as part of the OPAL project, a physical-picture equation of state was developed for the first time suitable for stellar models". It looks like the most pertinent reference is F. J. Rogers, F. J. Swenson, and C. A. Iglesias, Astrophysical Journal v.456, p.902 (1996). The abstract is rather illuminating, in light of CC's repeated claims: Originally Posted by Rogers et al. OPAL opacities have recently helped to resolve a number of long-standing discrepancies between theory and observation. This success has made it important to provide the associated equation-of-state (EOS) data. The OPAL EOS is based on an activity expansion of the grand canonical partition function of the plasma in terms of its fundamental constituents (electrons and nuclei). The formation of composite particles and many- body effects on the internal bound states occur naturally in this approach. Hence, pressure ionization is a consequence of the theory. In contrast, commonly used approaches, all of which are based on minimization of free energy, are forced to assert the effect of the plasma on composite particles and must rely on an ad hoc treatment of pressure ionization. Another advantage of the OPAL approach is that it provides a systematic expansion in the Coulomb coupling parameter that includes subtle quantum effects generally not considered in other EOS calculations. Tables have been generated that provide pressure, internal energy, entropy, and a variety of derivative quantities. These tables cover a fairly broad range of conditions and compositions applicable to general stellar-evolution calculations for stars more massive than ˜0.8 Msun. An interpolation code is provided along with the tables to facilitate their use. YMMV of course, but I read this as saying that the OPAL EOS includes a great deal more than "just the ideal gas laws". If so, what is the fundamental cause of the, um, disconnect between CC's claims and reality?
'13-07-28, 11:05 ben m	Originally Posted by Charles Chandler I'm not questioning whether or not supersonic flows can be "simulated". I'm questioning whether or not the "simulations" took into account that by the laws of fluid dynamics, the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. What law of fluid dynamics is that, CC? Who discovered it and where did you learn about it? Perhaps you need to go teach this law to some important fluids that seem not to have heard of it. http://en.wikipedia.org/wiki/Rocket_engine_nozzle Quote: In essence, Dalsgaard is saying that the only significance of the nonideality is that it can be used to track down some of the wave transmission speed anomalies. The point is, you're not merely saying that Dalsgaard misuses the equation of state the he actually obtained from the laws of physics, i.e. the nearly-ideal EOS. You're saying that he obtained the wrong EOS entirely, because the real EOS must be incompressible, according to your handwaving and intuition for fluids. Quote: I'll tell you why. The average magnetic field is only 1 Gauss (which isn't much), but more tellingly, the behaviors of the granules are the same, regardless of the polarity and strength of the magnetic fields. This would tend to mean that the magnetic force isn't a factor, don't you think? MHD is not simply about flow in an external magnetic field, as though you were tracking particles through a spectrometer. It's also about internal magnetic fields, which provide wave modes and couplings and forces that aren't present in nonconducting fluids. Anyway, 1g is NOT a small or ignorable field amplitude. What's the gyroradius of an 0.5 eV electron in a 1g field, CC? I repeat, what makes you say MHD is "ad hoc"?
'13-07-28, 11:17 dasmiller	Originally Posted by Charles Chandler I'm questioning whether or not the "simulations" took into account that by the laws of fluid dynamics, the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. You keep saying that, but it doesn't seem nearly as significant to me as it does to you. True, if you have a gas-filled pressure vessel in a vacuum, and you punch a hole in it, you get a standing shock wave across the hole with gas flowing out at the local speed of sound. That mechanism is nothing at all like convection. The temperature of a gas comes from the motion of the individual molecules (or atoms/nuclei/electrons in a plasma) with respect to their neighbors; the speed of sound is roughly the rms of the average speed of the particles with respect to their neighbors. The bulk motion of clump of gas is simply the result of the various forces (most obviously pressure differentials and inertia) acting on it. As far as I can tell, you're asserting that the generally-accepted model's external forces on a clump of gas could not accelerate that clump beyond the point where its velocity with respect to the local rotational rate is greater than the rms of the average velocity of the constituent particles with respect to their neighbors. Is that correct? And if so . . . why would you assert that? ETA: sorta ninja'd by ben
'13-07-28, 11:25 Charles Chandler	Originally Posted by DeiRenDopa I find it very hard to square CC's characterizations of "the mainstream view" of solar physics with what's in that 2003 paper. Please be specific. Originally Posted by Wikipedia: Standard Solar Model A more realistic description of the uppermost part of the convection zone is possible through detailed three-dimensional and time-dependent hydrodynamical simulations, taking into account radiative transfer in the atmosphere. Such simulations successfully reproduce the observed surface structure of solar granulation, as well as detailed profiles of lines in the solar radiative spectrum, without the use of parametrized models of turbulence. Originally Posted by DeiRenDopa Got that CC? I'm not questioning whether or not supersonic flows can be "simulated". I'm questioning whether or not the "simulations" took into account that by the laws of fluid dynamics, the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. Originally Posted by Rogers et al. Another advantage of the OPAL approach is that it provides a systematic expansion in the Coulomb coupling parameter that includes subtle quantum effects generally not considered in other EOS calculations. Originally Posted by DeiRenDopa YMMV of course, but I read this as saying that the OPAL EOS includes a great deal more than "just the ideal gas laws". That's correct — the OPAL EOS includes more than just the ideal gas laws. I never said that the OPAL EOS is based entirely on the ideal gas laws. I said that Dalsgaard Model S is based entirely on the ideal gas laws. The OPAL EOS includes factors not considered in other EOS calculations, such as Dalsgaard Model S. Why don't other EOS calculations include such factors? Because they consider them to be too slight. And that's what I'm questioning. The reason for the questioning is that the supersonic hydrodynamics of the solar surface cannot be rationalized in any Newtonian regime. There shouldn't be a boundary there, much less one with supersonic flows.
'13-07-28, 12:18 Charles Chandler	Originally Posted by ben m What law of fluid dynamics is that, CC? Who discovered it and where did you learn about it? Perhaps you need to go teach this law to some important fluids that seem not to have heard of it. http://en.wikipedia.org/wiki/Rocket_engine_nozzle Where is the gas expanding faster than its own speed of sound? The thrust of a rocket engine comes from the fact that the exhaust is moving faster than the ambient air — sometimes super- or hyper-sonically — relative to the ambient air. But what about relative to itself? The action of the rocket nozzle is to compress the air, which increases the pressure, because it increases the temperature. That gets the temperature way above the combustion temperature, and it gets the particle velocity way above the particle velocity at combustion temperature. But the net particle velocity is the definition of the speed of sound. So unless accelerated by a non-Newtonian force (e.g., a charged particle in an electric field), net particle velocity in excess of the speed of sound is not possible, by definition. Originally Posted by ben m You're saying that [Dalsgaard] obtained the wrong EOS entirely, because the real EOS must be incompressible, according to your handwaving and intuition for fluids. Well, not entirely incompressible, depending on what you mean by that. I need to improve the accuracy of the statements on my website, because I do use room-temperature liquid densities in the first round of calculations, and the reality is a lot more complex. I said in post #25: Originally Posted by Charles Chandler There isn't a fixed [compressibility] limit — it varies with temperature. At room temperature, hydrogen becomes incompressible at roughly 70 kg/m3. At 6000 K, the limit is something like 600 kg/m3. If the solar density gradient was Newtonian (i.e., if the Coulomb barrier wasn't a factor), the first limit would be hit at about 0.85 R⊙, and the second would be hit at about 0.55 R⊙. If forces other than gravity are compressing the plasma, these limits are hit closer to the surface. And that assumes that the Sun is comprised primarily of hydrogen. Heavier elements have more degrees of ionization, thus have many more "compressibility limits" (depending on ionization, which usually depends on temperature). But yes, I'm saying that incompressibility has to be taken into account, though it's not any sort of simple incompressibility, and the limits are definitely not the room-temperature liquid densities. Originally Posted by ben m I repeat, what makes you say MHD is "ad hoc"? And I repeat, because the behaviors of the granules are the same, regardless of the polarity and strength of the magnetic fields. Originally Posted by dasmiller True, if you have a gas-filled pressure vessel in a vacuum, and you punch a hole in it, you get a standing shock wave across the hole with gas flowing out at the local speed of sound. That mechanism is nothing at all like convection. Right — convection is the result of density differences, producing velocities way below the speed of sound.
'13-07-28, 12:27 DeiRenDopa	I'll start this post with a comment by ben m, because I think it's very apt for what follows: Originally Posted by ben m Sorry to use the C-word, but that is straight-up crackpot reasoning. [...] When an amateur/intuitive calculation disagrees with a detailed professional calculation, it generally means that the amateur is wrong. Recall post #14, and what CC wrote: "Here is an introduction to the solar model that I'm developing, posted here to encourage critical reviews." Well, here's something from his webpage, the first part of the section called "Energy": Originally Posted by CC The first test will be to see if this model can identify fully physical energy sources capable of producing the 3.86 × 1026 watts of EM radiation1 that continually stream out of the Sun. Sounds good, doesn't it? Let's read on ... Quote: The standard model asserts that the sole energy source is hydrogen fusion in the core, but this is questionable. A reliable estimate of the nuclear fusion rate in the Sun can be made by counting the electron neutrinos that are produced. By this measure, fusion is only responsible for 1/3 of the Sun's power.2 Researchers committed to the "fusion furnace" model consider this to be proof that neutrinos spontaneously change flavor, such that in the time it takes them to reach the Earth, 2/3 of the electron neutrinos have changed into muon or tau neutrinos, which are not detectable.3 But modifying a theory to absorb an anomaly, and then calling the anomaly proof of the theory, is circular reasoning. Independent proof has not been established, and without it, that's just an unverified hypothesis. If we take the data at face value, we are still in search of something that can cause 2/3 of the solar output. CC's ref #2 is a dead end; however this is what it is intended to refer to: "Nobel Lecture: Birth of neutrino astrophysics" (the full text PDF is not behind a paywall). Is CC's assertion ("By this measure, fusion is only responsible for 1/3 of the Sun's power") consistent with Nobel Laureate Masatoshi Koshiba's paper? I'll let you be the judge. Ref #3 is a Scientific American article, from March 2003. So, time for some "critical review": why did you cite documents only from 2003, CC? What efforts did you make, to determine the extent of "independent proof" (your term) of neutrino oscillations? In particular, did you actually read Koshiba's paper, the one you cited, right through to the end? If you did, what did you make of this? "The obtained oscillation parameters, [...], are in good agreement with the solar neutrino result of Fig. 17."
'13-07-28, 12:41 DeiRenDopa	Egg. Originally Posted by Charles Chandler Please be specific. I was. Please re-read what I wrote. Carefully. Quote: That's correct — the OPAL EOS includes more than just the ideal gas laws. I never said that the OPAL EOS is based entirely on the ideal gas laws. I said that Dalsgaard Model S is based entirely on the ideal gas laws. The OPAL EOS includes factors not considered in other EOS calculations, such as Dalsgaard Model S. Why don't other EOS calculations include such factors? Because they consider them to be too slight. And that's what I'm questioning. So, let's go over this one more time. What EOS does Model S ("the 1996 paper") incorporate? The OPAL EOS ("The model used the OPAL equation of state"). Is the OPAL EOS "based entirely on the ideal gas laws"? No. Taking Christensen-Dalsgaard et al. at their word, is Model S "based entirely on the ideal gas laws"? No. Quote: The reason for the questioning is that the supersonic hydrodynamics of the solar surface cannot be rationalized in any Newtonian regime. There shouldn't be a boundary there, much less one with supersonic flows. In light of the, um, mis-characterizations which seem rather rife (in what you write), how about you take the time to state - clearly - what you mean, in this context, by a "Newtonian regime"? Also, in "[t]here shouldn't be a boundary there", are you referring to something in a spherically symmetric model (such as a SSM)?
'13-07-28, 12:47 dasmiller	Originally Posted by Charles Chandler Where is the gas expanding faster than its own speed of sound? Usually just past the throat of the nozzle. Seriously, how do you think supersonic wind tunnels work? No more energy is injected into the fluid after it goes through the throat, and yet the fluid accelerates well beyond supersonic. Quote: The thrust of a rocket engine comes from the fact that the exhaust is moving faster than the ambient air — sometimes super- or hyper-sonically — relative to the ambient air. But what about relative to itself? now, think about that for a moment. "relative to itself?" By definition, it's not moving relative to itself. Quote: The action of the rocket nozzle is to compress the air, which increases the pressure, because it increases the temperature. The rocket nozzle allows the gas to expand, which cools it and lowers its pressure. Are you thinking of the combustion chamber? Quote: That gets the temperature way above the combustion temperature, and it gets the particle velocity way above the particle velocity at combustion temperature. But the net particle velocity is the definition of the speed of sound. No, the speed of sound is defined as the speed that sound waves propagate through the medium. FWIW, the speed of sound is related to the rms particle speed by a factor of around 1.4 (it varies a bit). Quote: So unless accelerated by a non-Newtonian force (e.g., a charged particle in an electric field), net particle velocity in excess of the speed of sound is not possible, by definition. Repeating the phrase "by definition" when used in the context of things that are not mentioned in the definition does not strengthen your point. Quote: Right — convection is the result of density differences, producing velocities way below the speed of sound. While I agree that one could not design a hot-air balloon that would rise supersonically in earth's atmosphere (if it had only buoyancy to propel it), it's not obvious to me that in a vastly larger, more complex system with updrafts-within-updrafts that supersonic flow is impossible. Certainly in Earth's atmosphere, we get wind speed that are far, far higher than the thermal updraft speeds. Also, bear in mind that in convection, the rising fluid cools. As it cools, its speed of sound drops ("by definition!"). Thus, if you have a long rising column of fluid, even if the whole column is moving at a constant speed, the fluid at the top may be supersonic even though the fluid at the bottom is subsonic*. *I have no idea whether this happens on the sun.
'13-07-28, 12:55 DeiRenDopa	Originally Posted by Charles Chandler But yes, I'm saying that incompressibility has to be taken into account, though it's not any sort of simple incompressibility, and the limits are definitely not the room-temperature liquid densities. When do you expect to update your calculations, and post the results? Will you be editing your webpage, retaining the current version for future comparison? In your research to update the "incompressibility" values, will you be using sources such as reports of inertial confinement fusion experiments (such as this one)? I ask because in some of these I read that hydrogen has been successfully compressed to densities of > 100 grams per cubic centimeter.
'13-07-28, 12:57 ben m	Originally Posted by Charles Chandler I'm not questioning whether or not supersonic flows can be "simulated". I'm questioning whether or not the "simulations" took into account that by the laws of fluid dynamics, the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. See, I don't think "supersonic convection" is obviously an oxymoron. I'm not sure whether it is. The way I would resolve the question is by applying the laws of physics (mathematically, not intuitively) and seeing whether supersonic motion ever pops out. A simulation is just "using a computer to apply the laws of physics numerically", a process which can easily be just as accurate as "using pencil and paper to apply the laws of physics analytically", and far, far far more accurate than "Ask Charles Chandler to think it through intuitively". If this particular simulation pops out with supersonic-flow as a valid solution, then that sounds reasonable to me. Originally Posted by Charles Chandler Where is the gas expanding faster than its own speed of sound? Nope, the gas exits the nozzle faster (with respect to the nozzle walls) than the speed of sound in the exhaust gas itself. Your intuition says this impossible? Your intuition is wrong, or you're applying it to oversimplified geometries, or something. Quote: But the net particle velocity is the definition of the speed of sound. So unless accelerated by a non-Newtonian force (e.g., a charged particle in an electric field), net particle velocity in excess of the speed of sound is not possible, by definition. See, here's part of the oversimplification. The speed of sound is the speed of pressure wave propagation, relative to the gas rest frame. If the wind is blowing west at 100 m/s, sound will propagate west at 400 m/s or east at 200 m/s. Quote: But yes, I'm saying that incompressibility has to be taken into account, though it's not any sort of simple incompressibility, and the limits are definitely not the room-temperature liquid densities. Daalsgard does take the compressibility into account ... the correct compressibility, the one found by applying the laws of physics in great detail. Daalsgard does not take the Chandler-derived-incompressibility into account---neither the simple one nor any more complex one---and rightly so, because this incompressibility appears to be nonsense, derived with nonsensical methods.
'13-07-28, 14:54 DeiRenDopa	What follows isn't entirely new, in terms of critical commentary in this thread, of CC's idea, but some aspects are. Originally Posted by CC Whenever an element is compressed into a liquid and then additional pressure is applied, the liquid gets ionized.4From this we can conclude that the core and the lower half of the convective zone are positively charged (green in Figure 3). (bold added) We can? Let's see what ref #4 is. "Saumon, D.; Chabrier, G., 1992: Fluid hydrogen at high density: Pressure ionization. Physical Review A, 46 (4): 2084-2100". How - CC - does it follow, from this, "that the core and the lower half of the convective zone are positively charged"? In detail please. Originally Posted by CC But the charge separation mechanism is gravity, In a plasma, the Pannekoek-Rosseland effect is just such a mechanism. But CC has already ruled that out. So he must be referring to an entirely different - new? - mechanism. If so (please confirm CC), what is it?
'13-07-28, 14:59 Charles Chandler	Originally Posted by DeiRenDopa So, let's go over this one more time. What EOS does Model S ("the 1996 paper") incorporate? The OPAL EOS ("The model used the OPAL equation of state"). Where did Dalsgaard say that he used the OPAL EOS to calculate densities? This is getting ridiculous. Originally Posted by DeiRenDopa In light of the, um, mis-characterizations which seem rather rife (in what you write), how about you take the time to state - clearly - what you mean, in this context, by a "Newtonian regime"? "Newtonian regimes" include inertial, gravitational, and frictional forces. Originally Posted by DeiRenDopa Also, in "[t]here shouldn't be a boundary there", are you referring to something in a spherically symmetric model (such as a SSM)? There is no distinct boundary in Dalsgaard Model S — the density smoothly tapers off to nothing. Originally Posted by dasmiller Also, bear in mind that in convection, the rising fluid cools. As it cools, its speed of sound drops ("by definition!"). Thus, if you have a long rising column of fluid, even if the whole column is moving at a constant speed, the fluid at the top may be supersonic even though the fluid at the bottom is subsonic*. *I have no idea whether this happens on the sun. That's a legitimate point, and it "could" explain the 2 km/s updrafts in solar granules, as momentum developed at higher temperatures and under higher pressures, where the updrafts began. But then these supersonic updrafts mushroom at the top, where the flow splays outward, and then the flow heads back into the Sun in downdrafts around the outsides of the granules. Curiously, the downdrafts have been clocked at over 7 km/s, and that's in the intergranular lanes, which are only 700 km lower than the tops of the granules. So the speed more than triples in the process of pulling a 180 degree turn, from an updraft back into a downdraft, and this is all in plain sight. Negative buoyancy cannot create hypersonic velocities, and there is nothing else to which to attribute the acceleration (without considering non-Newtonian forces). And to anticipate DeiRenDopa's argument, the OPAL EOS considers non-Newtonian forces in the estimation of opacities, but the Model S EOS does not consider them in the estimation of the densities, which I contend is incorrect. Originally Posted by DeiRenDopa When do you expect to update your calculations, and post the results? That could take years! But I'll be sure to let you know. Originally Posted by DeiRenDopa Will you be editing your webpage, retaining the current version for future comparison? Yes — registered users can see side-by-side comparisons of versions, going back to the first version submitted. Originally Posted by DeiRenDopa In your research to update the "incompressibility" values, will you be using sources such as reports of inertial confinement fusion experiments (such as this one)? I ask because in some of these I read that hydrogen has been successfully compressed to densities of > 100 grams per cubic centimeter. You have to compress it more than that to fuse it into helium, so there's no doubt that higher densities are possible. The question is, "What force is necessary to achieve such densities?" Originally Posted by ben m A simulation is just "using a computer to apply the laws of physics numerically", a process which can easily be just as accurate as "using pencil and paper to apply the laws of physics analytically", and far, far far more accurate than "Ask Charles Chandler to think it through intuitively". So what happens when a computer tries to run code that doesn't take all of the applicable laws of physics into account? Do you get a syntax error or something? Computers can certainly be used to do the heavy-duty number crunching inherent in physics simulations, but just because it was done on a computer doesn't mean that it was a physics simulation. In gaming software, are they running out Newtonian mechanics in real time, or is that all just quick-n-dirty algorithms that fake it? If so, how did they ever get the code to compile? Or does the compiler know whether you're a game developer or a physicist, and throw different errors accordingly? (Syntax error for game developers: ERROR! Those colors are aweful! Syntax error for physicists: ERROR! That formula doesn't include the Coulomb force! ) In reality, there is an acronym used by computer programmers that you should learn: GIGO. This stands for "garbage in, garbage out". So when you say, "If this particular simulation pops out with supersonic-flow as a valid solution, then that sounds reasonable to me," you obviously are just assuming that if it came out, it has to be good, not realizing that the programmer might have fed in some garbage. Being a computer programmer, I know better than to make assumptions about what was fed in, to produce the desired output. Originally Posted by ben m The speed of sound is the speed of pressure wave propagation, relative to the gas rest frame. If the wind is blowing west at 100 m/s, sound will propagate west at 400 m/s or east at 200 m/s. Right. But if you're talking about convection, you're talking about acceleration from a resting position, and there isn't any nozzle.
'13-07-28, 15:46 DeiRenDopa	Originally Posted by Charles Chandler Where did Dalsgaard say that he used the OPAL EOS to calculate densities? On page 5, of the PDF in the link you yourself supplied. As I already said. Quote: This is getting ridiculous. I know; it requires a reading comprehension sufficient to recognize what a footnote is, and find that footnote (on page 17, in this case): "The model used the OPAL equation of state and opacities (34)" Quote: "Newtonian regimes" include inertial, gravitational, and frictional forces. Thanks for the clarification. So anything involving modelling of plasmas is, by your definition, not in any Newtonian regime, right? Because any modelling of plasmas must, by definition, incorporate electromagnetic forces, right? Also, anything involving modelling of heat transfer, radiation, and so on, is - again, by your definition - not in any Newtonian regime, right? Quote: There is no distinct boundary in Dalsgaard Model S — the density smoothly tapers off to nothing. Well thanks. When may I expect an answer to the question I actually asked?
'13-07-28, 15:48 ben m	Quote: Right. But if you're talking about convection, you're talking about acceleration from a resting position, and there isn't any nozzle. So much for your assertive "by definition!" statements, anyway.
'13-07-28, 15:58 dasmiller	Originally Posted by Charles Chandler Curiously, the downdrafts have been clocked at over 7 km/s, and that's in the intergranular lanes, which are only 700 km lower than the tops of the granules. So the speed more than triples in the process of pulling a 180 degree turn, from an updraft back into a downdraft, and this is all in plain sight. Negative buoyancy cannot create hypersonic velocities, and there is nothing else to which to attribute the acceleration (without considering non-Newtonian forces). So, based on your analysis, what is the maximum possible speed for a dense gas falling 700 km through a lighter gas in a 28g field?
'13-07-28, 19:05 Charles Chandler	Originally Posted by Charles Chandler Where did Dalsgaard say that he used the OPAL EOS to calculate densities? Originally Posted by DeiRenDopa On page 5, of the PDF in the link you yourself supplied. As I already said. I saw that. Now where did Dalsgaard say that he used the OPAL EOS to calculate densities? The paper only says that the OPAL EOS was incorporated for that one section, entitled "Some properties of solar oscillations". If it was an integral aspect of Model S, Dalsgaard wouldn't have worded it that way. Originally Posted by DeiRenDopa So anything involving modelling of plasmas is, by your definition, not in any Newtonian regime, right? Because any modelling of plasmas must, by definition, incorporate electromagnetic forces, right? Not necessarily. Originally Posted by DeiRenDopa Also, anything involving modelling of heat transfer, radiation, and so on, is - again, by your definition - not in any Newtonian regime, right? Radiation is non-Newtonian, but heat transfer by convection or conduction is Newtonian. Originally Posted by DeiRenDopa When may I expect an answer to the question I actually asked? What question is that? Originally Posted by dasmiller So, based on your analysis, what is the maximum possible speed for a dense gas falling 700 km through a lighter gas in a 28g field? Just by the force of gravity, minus friction, would be one question, but not a question relevant to the study of granules. There the question is, "How much force does it take to accelerate plasma downward, from a (vertically) stopped position, achieving 7 km/s in only 700 km of travel?" The answer is, "I don't know."
'13-07-28, 19:35 Reality Check	Originally Posted by Charles Chandler Nevertheless, I still stand by my assertion that the solar density gradient is non-Newtonian. Sorry, Charles Chandler, but you re still jumping to conclusions from a stance of ignorance ! The supersonic hydrodynamics of photosphere granules, and the occasional post-flare s-waves, are rationalized within the standard models regardless of what physics you imagine these models to contain. Extending your ignorance to MHD is fairly ridiculous. Scientists invoke MHD which ignores electric fields because they can be fond from the magnetic fields. They do identify the magnetomotive forces which are electric sheets (this is 3D not the 2D of wires) and changes in magnetic fields. They do identify the electromotive forces which are changes in magnetic fields and electric sheets. The actual science has many answers which you are ignoring, Charles Chandler. The actual science directly addresses many issues which you are ignoring, Charles Chandler.
'13-07-28, 19:50 Reality Check	Originally Posted by Charles Chandler Can anyone refute the claim that the observations of supersonic hydrodynamic flows on the surface of the Sun are proof of non-Newtonian density gradient? This is indeed in addition to the creationist "Gish gallop" tactic that the thread has threatened to turn into, Charles Chandler. This is your assertion. It is not up to us to refute it - it is up to you to support it. What we can say is that the standard models (regardless of the physics involved) can match the observations of supersonic hydrodynamic flows on the surface of the Sun. Detection of supersonic horizontal flows in the solar granulation Magnetic field intensification: comparison of 3D MHD simulations with Hinode/SP results Hydromagnetic structure of the chromosphere near the supergranule boundary (but for supergranules!) Supersonic flows in the solar photosphere - general supersonic flows (and unexpected!) may be of interest. Fast horizontal flows in a quiet sun MHD simulation and their spectroscopic signatures The paper you cited shows that the density gradient in that paper was derived from "purely Newtonian" equations of state. No one should be idiotic enough to suggest that the measured supersonic flows are illusions basics on the irrelevant fact the photosphere is relatively thin and gives the illusion of a distinct surface. Originally Posted by Charles Chandler I doubt that I'll get an answer, because in the mainstream, there isn't one. The reality is that you have got an answer: that in the mainstream (look at the papers cited above), there is one - you have just not bothered to look it up.
'13-07-28, 19:56 Reality Check	Originally Posted by Charles Chandler ...the fastest that a fully unrestrained gas/plasma (i.e., one that is not being down by the force of gravity) can flow into a pure vacuum is the speed of sound, and that's by definition. So "supersonic convection" is an oxymoron. And the repeated ignorance exposed in that statement is getting a bit shorter than "oxymoronic" . This is not a "fully unrestrained gas/plasma". This is not a "flow into a pure vacuum". Supersonic flows in granules are flows of plasma within plasma, Charles Chandler ! The granules are convection cells within the photosphere.
'13-07-28, 20:06 Reality Check	Originally Posted by Charles Chandler Radiation is non-Newtonian, but heat transfer by convection or conduction is Newtonian. This is another problem with amateurs - they tend not to us terminology correctly. Charles Chandler, non-Newtonian has a few meanings, none of which fully match your context. The context implies non-Newtonian fluid Quote: A non-Newtonian fluid is a fluid whose flow properties differ in any way from those of Newtonian fluids. Most commonly the viscosity (measure of a fluid's ability to resist gradual deformation by shear or tensile stresses) of non-Newtonian fluids is dependent on shear rate or shear rate history. For example, Silly Putty.
'13-07-28, 20:12 dasmiller	Originally Posted by Charles Chandler Just by the force of gravity, minus friction, would be one question, but not a question relevant to the study of granules. For what it's worth, if it was purely ballistic, it would be about 20 km/s. I agree that the various drag forces certainly can't be neglected, but 20 km/s means that the downflow can lose 87% of its potential energy to friction and still hit 7 km/s. And that's for the portion of the downflow which is least affected by friction. Quote: There the question is, "How much force does it take to accelerate plasma downward, from a (vertically) stopped position, achieving 7 km/s in only 700 km of travel?" The answer is, "I don't know." Actually, the way you worded it, the math is pretty simple (you'd need about 35N/kg or 3.6 gs), but I don't think that's the problem you meant to pose. Estimating the net forces on gases circulating over the sun is a vastly more difficult problem, and, like you, I simply don't know. But while I try to avoid making broad assertions on subjects where I lack knowledge . . . ahem.
'13-07-28, 20:17 Reality Check	Originally Posted by Charles Chandler OK, I'm done trying to slog through your derogatory remarks, to try to find the legitimate questions. There have been a few, but most of your posts have been rhetorical, vaguely worded, and thoroughly infused with hatred, and I just don't have the time for any of that. Wow - what a lot derogatory remarks, rhetorical, vaguely worded, and thoroughly infused with hatred text, Charles Chandler ! What I said was that you are acting more like a crank rather than a scientist in this statement Quote: Originally Posted by Charles Chandler First, I don't do models that generate data (which are unbelievably well-predicted by the model) the way scientists do. If something can be directly observed, I just go with the observations, and then challenge the model to explain the data. Anyway, I first answered the question in post #79. Your post #79 does not contain any explanation of supersonic flows from your model. There are no issues with supersonic flows in the existing models. I do tend to call a spade a spade (not a shovel). Thus an unsupported statement that X happens just because someone wants X to happen is a fantasy. When the science refutes that X happens, someone ignores that science and just repeats the assertion then that fantasy can be described as a delusion. Unfortunately for your ideas, other people know that my questions are legitimate and address the physics that you are ignoring. So maybe they will quote my questions to remind you about the physics. My legitimate question about your model is Charles Chandler: Please use your model to explain the supersonic flows in granules First asked 26 July 2013 - 3 days and counting.
'13-07-28, 20:33 Reality Check	Charles Chandler Plasmas already have free electrons and these do not separate except in very special conditions (double layers). What is special about these compressive ionization electrons that makes them form double layers? Alternately show that DL's form and persist in the conditions inside of the Sun. First asked 26 July 2013 - 3 days and counting. Charles Chandler: citations that stellar plasma is supercritical fluid First asked 26 July 2013 - 3 days and counting. And this post Originally Posted by Reality Check CFDLs are impossible in stellar conduction zones because Conduction zones are turbulent thus no layers of anything can form. Double layers in stellar plasma have scales of 10-11 meters (solar core) to 10 meters (solar wind). Double layers are double layers () not multiple layered structures as you imagine. Double layers do not magically form wherever you want them to form! They need specific conditions to form. Double layers are not stable has been quite ignored so I will separate it into questions: Charles Chandler Double layers are not stable. Please explain how (or if!) the CFDLs persist when DLs have relatively short lifetimes. Double layers are double layers () not multiple layered structures as you state. As far as I can see, there are no electrostatic forces outside of a layer of a DL to create more layers unless you forget about the existence of the other layer. That is in fact how DLs form - the electrons are moved far enough away from the positive ions to balance out the electrostatic forces. Please cite sources for DLs having multiple layers. Double layers in stellar plasma have scales of 10-11 meters (solar core) to 10 meters (solar wind). Please state and justify the scale of the CFDLs. First asked 29 July 2013 - 0 days and counting. Someone may want to quote or ask these questions since Charles Chandler is ignoring me.
'13-07-28, 21:10 Charles Chandler	Originally Posted by dasmiller For what it's worth, if it was purely ballistic, it would be about 20 km/s. I agree that the various drag forces certainly can't be neglected, but 20 km/s means that the downflow can lose 87% of its potential energy to friction and still hit 7 km/s. And that's for the portion of the downflow which is least affected by friction. Actually, the way you worded it, the math is pretty simple (you'd need about 35N/kg or 3.6 gs), but I don't think that's the problem you meant to pose. For solar plasma, I'd be happy to neglect the drag forces, since these are generally negligible. And you're right that the innermost plasma would get the least friction. But you're also right that I worded the question poorly — you'd need 35 N/kg of negative buoyancy (or force difference between it and its neighbors). And that's where the problem is. Originally Posted by dasmiller But while I try to avoid making broad assertions on subjects where I lack knowledge . . . ahem. You know, I take a comment like that more seriously than the floggings I've been getting from elsewhere. Floggings just make me want to fight back, but a gentle remark from a knowledgeable person is something to think about. My compliments. But despite my ignorance, I still maintain that I have legitimate questions that don't seem to have good answers. For example, another non-Newtonian behavior of the photosphere is the s-waves that sometimes occur after a solar flare. The waves captured by SOHO on 1996-07-09 were particularly pronounced. First, s-waves only occur on the boundary between two distinctly different densities, which is unexplained in the Dalsgaard model. Second, the initial wave speed was 10 km/s, which is supersonic. Third, the waves accelerated, ultimately reaching 100 km/s before disappearing. So what's the explanation for all of that?
'13-07-29, 04:41 phunk	Originally Posted by Charles Chandler For solar plasma, I'd be happy to neglect the drag forces, since these are generally negligible. And you're right that the innermost plasma would get the least friction. But you're also right that I worded the question poorly — you'd need 35 N/kg of negative buoyancy (or force difference between it and its neighbors). And that's where the problem is. You are aware that the sun's gravity at the surface is 274 N/kg, right?
'13-07-29, 06:14 Charles Chandler	Originally Posted by phunk You are aware that the sun's gravity at the surface is 274 N/kg, right? Yes. Now consider this, from Continuous and line spectra of granules and intergranular lanes (with my bolding): Originally Posted by Z. Suemoto, E. Hiei, Y. Nakagomi Temperature and velocity structures above granules and intergranular lanes were studied on spectrograms covering Caii H and K lines. In agreement with our earlier results, it was confirmed more quantitatively that there appear two kinds of bright continua, one in the outer wings (granular continuum) and the other in the inner wings (temporarily called K0-continuum) of Caii H and K lines, and that these two kinds of bright continua are located more or less in a complementary fashion. Further, it was found that the bright K0-continuum is well associated with higher central residual intensity of absorption lines. These facts suggest that in the upper photosphere of, say, τ high temperature regions in the intergranular lanes. Motions above granular regions are essentially upwards, whereas those of intergranular regions are predominantly downwards, and in the uppermost photosphere the motions become more random. How do you get negative buoyancy with higher temperatures?
'13-07-29, 06:39 DeiRenDopa	Originally Posted by Charles Chandler Originally Posted by CC Where did Dalsgaard say that he used the OPAL EOS to calculate densities? Originally Posted by me On page 5, of the PDF in the link you yourself supplied. As I already said. I saw that. Now where did Dalsgaard say that he used the OPAL EOS to calculate densities? The paper only says that the OPAL EOS was incorporated for that one section, entitled "Some properties of solar oscillations". If it was an integral aspect of Model S, Dalsgaard wouldn't have worded it that way. Two words CC, hermeneutical scholasticism (I believe it was D'rok who introduced this, in these kinds of settings). But we don't have to become biblical scholars literary detectives to resolve this: you have Model S, you have the tools ... you already checked that, in Model S, the ideal gas law holds at every radius, right? I mean, you certainly didn't want to be caught with egg on your face, so you did your own analysis of the data (the Model S table you include in your website), and confirmed that the ideal gas law rules, right? OK, so would you be so kind as to share with us the results of your independent checking? Quote: Quote: So anything involving modelling of plasmas is, by your definition, not in any Newtonian regime, right? Because any modelling of plasmas must, by definition, incorporate electromagnetic forces, right? Not necessarily. Why not? Quote: Quote: Also, anything involving modelling of heat transfer, radiation, and so on, is - again, by your definition - not in any Newtonian regime, right? Radiation is non-Newtonian, but heat transfer by convection or conduction is Newtonian. Hmm, so a density gradient in a model which incorporates radiative transport cannot, by your definition, be Newtonian, right?