Unless you can explain to me why I would not expect to observe neutrino emissions from the high energy events in the solar atmosphere, I see no reason to believe that they do not occur there, or that I would not see surface related "hits" from such events. Lots of different kinds of high energy cosmic ray interactions might release neutrinos in the upper atmosphere of the sun. I could almost be logically certain to observe more than just a single point source of neutrinos from the sun's core.
Alas Michael, and I say this with genuine respect and kindness, the history of science is littered with faux pas based upon arguments of personal credulity. Unless your wording here is a mere literary device, that type of approach is not generally considered a convincing route to better definition of the physical world.
Well, I certainly respect the fact that my opinion is simply a logical and educated "guess" based on known physical processes (gamma rays) and their emission patterns (neutrinos). This "guess" lacks mathematical expression at this point in time so in the sense that it's not mathematically expressed, I'm sure it's not a particularly compelling argument to you right now.
I personally think that one of the most difficult aspects of EU theory in a general sense is that it is extremely difficult to quantify. In many respects it is far more "complicated" than standard theory, and therefore it's harder to quantify EU theory in robust mathematical terms. I think that is why I get particularly dismayed when people like Nereid handwave away some of the best mathematical efforts to quantify EU theory.
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While all theories have some type of mental model within, the main virtue of their inner intellectual mechanics is to construct a framework for *quantitative* prediction.
I hear you on this point loud and clear. That seems to be the whole intent behind Birkeland's work in fact. He experimented with a lot of different variables so that he could begin to quantify the processes and begin to quantify the amount of "flying electric ions" and electrons in his experiments so that he could begin to "predict" what that might equate to at large scales.
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A terrific example is Tycho Brahe who was one of the first to suggest and enact our 'modern' program - to measure some phenomena to the best accuracy available, in order to then present a body of data as a benchmark for comparison of any candidate models that are presented as purporting to explain said phenomena.
Well, that is why I so profoundly appreciate the THEMIS program and other programs like it that attempt to quantify these electrical flow patterns. IMO that is the most important type of work that can be done to begin to quantify the electron flows within the plasmas of spacetime. The more we can learn about our own solar system, the more likely we will be able to predict the behaviors of other solar systems and other objects in space.
On March 23, 2007 the 5 THEMIS spacecraft observed the onset of a substorm while located in the dusk flank of the magnetoshere. The substorm was also observed in ground-based data and in Polar UVI images. Using Wind data to drive the OpenGGCM we conducted a simulation study of this substorm. The simulation clearly shows the substorm characteristics, such as the current wedge and expansion of the aurora. In this paper we compare the OpenGGCM simulation with observations, address the magnetic mapping between THEMIS and the auroral features, and investigate whether this substorm was triggered by a sharp northward turn of the IMF.
The centerpiece of the NSF/GEM, program is the development of a Geospace General Circulation Model (GGCM), to be used as a research tool as well as a prototype for space weather forecasting models.
It was originally envisioned that the assembly of a GGCM would take place near the end of the GEM program, and that this GGCM would codify the progress that had been made during the GEM campaigns. However, in the late 90's it has become clear that such an approach may not be feasable. First of all, there are several possible approaches for constructing a GGCM, ranging from a strictly modular approach in which several regional models are coupled together, to approaches that builds on existing global MHD models. Second, no one model will fit all needs. What is required is rather a hierarchy of models of different sophistication and strengths. Third, and perhaps most important, the existing global MHD based models have improved dramatically such that they have become close to the envisioned GGCM. These developments have lead to the current three-phase plan for the GGCM implementation, which at this point abandons the idea of a grand unified GGCM in favor of a more flexible strategy that allows the parallel development of different approaches to a GGCM. These developments are documented in more detail in the GGCM Status Report.
The OpenGGCM is derived from the "UCLA Global MHD Model", originally developed by Jimmy Raeder at UCLA, and the NOAA/SEC CTIM (Coupled Thermosphere Ionosphere Model), originally developed by Tim Fuller-Rowell (while some of its components have a much longer heritage.) The OpenGGCM is now housed at the Space Science Center of the University of New Hampshire. It is considered a "Community Model." Potential users can request model runs from the Community Coordinated Modeling Center (CCMC) at the NASA Goddard Space Flight Center. The latest version is V3.0.
1. Magnetosphere: 3d fields of magnetic field, electric field, plasma density, flow velocity vector, and temperature or pressure. 2D fileds of the same quantities at prescribed planes (this allows for much higher cadence).
2. Ionosphere: Filed aligned currents, potential, Hall and Pedersen conductane, e- precipitation energy flux and mean energy.
3. Ground: magnetic peerturbations at mid- and high latitudes.
4. CTIM: 3D fields of various e-, ion, and neutral parameters: Ne, NfM2, hFm2, winds, ion/neutral temperature, N/O ratio, etc.
There's a paper by Ping Zhu on that website that you might find particularly interesting Michael ("Multiscale MHD Modelings of Substorm Onset in Earth's Magnetotail").
Would you mind taking a look at some of this material (including the code, if you're interested; it's open source), and commenting on the extent to which you feel it incorporates the 'right' parts of Birkeland's work? Also, if you feel any of the underlying physics is not 'qualified', would you mind outlining what, and why you feel it isn't?
* though, of course, he didn't know anything about the distinction between the magnetosphere and the IPM; nonetheless, all the astronomical and geophysical observables he sought to explain and model relate directly to the magnetosphere (except for visual waveband observations of the Sun, including the corona)
Ok, but you missed a step as it relates to "magnetic reconnection". This is what concerns me about "modern" astronomers. They seem to think that they can derive information about the forces of nature from *uncontrolled* observations. That is *not* how science works. If one intends to show that there is a unique energy release mechanism called "magnetic reconnection", one must demonstrate that "magnetic reconnection" is a unique form of energy release that is not related to electrical current flows that "reconnect" inside plasma. The only way one could do that is in a lab using *control mechanisms". *If* one can demonstrate that "magnetic reconnection" isn't a figment of collective imagination, *then* one can look at the THEMIS data and try to do some comparisons of the THEMIS data between Alfven's ideas, and your new lab measurements of "magnetic reconnection". Simply pointing to an uncontrolled observation will not demonstrate that validity of any theory, not Alfven's theories, or your own. Simply pointing to the observation and claiming it is consistent with "magnetic reconnection" is absurd, because no one can even explain what is unique about "magnetic reconnection" in the first place, and the author of MHD theory called the idea nonsense. More importantly, magnetic fields have been studied in a lab over and over again, and they never "reconnection" in any controlled test on earth.
First of all, when one is attempting to learn about a theory, in this case MHD theory, the Nobel prize winning author of the that theory is typically a good source and a reliable source of information. Obviously anyone *can* be wrong, but before we *assume* Alfven was wrong about magnetic reconnection, show me a controlled lab test that demonstrates "magnetic reconnection". In situ measurements won't tell us anything about the nature of "magnetic reconnection", but lab tests might. Maybe you're not giving Alfven enough credit?
If and when you come up with an physical (not metaphysical) explanation of the energy release in plasma that is unique to "magnetic reconnection", and you can identify and isolate what is different from magnetic reconnection and ordinary electrical interactions in plasma, and you can demonstrate that magnetic reconnection is responsible for some types of energy release *and* you can demonstrate that unique energy release signature is present in uncontrolled observations, *then* you can claim "magneticreconnectiondidiit". Without the lab work, it's pointless to point to an uncontrolled observation and claim "mynifitymathforumuladidiit".
So what did they decide was the unique energy release mechanism of "magnetic reconnection" that is uniquely and observationally different from ordinary electrical interactions in plasma?
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MSc Thesis Project: Influence of ion mass on plasma penetration across magnetic barriers
You mean like using electricity to shoot charged particles at double layers? Ever heard of induction Nereid?
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Different mechanisms, like impulsive penetration
That would simply be an induction event as far as I can tell.
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and magnetic reconnection,
What is magnetic reconnection? Describe it physically for us at an atomic physics level. What is the unique energy release mechanism of "magnetic reconnection"?
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have in the past few decades been suggested as possible means for the shocked solar wind plasma in the magnetosheath to enter the magnetosphere. Recent measurements from the Cluster spacecraft have shown that plasma indeed does penetrate the magnetopause.
In other words, charged particles come streaming off the sun and pass through the Earth's series of current carrying double layers? How is that at all consistent with "magnetic reconnection"?
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At KTH a series of experiments have been performed using a plasma gun that shoots a plasma at a transverse magnetic field.
A plasma gun? That uses *lots* of electricity to fire charged ions. How is that an example of "magnetic reconnection" as an energy source for these events? http://en.wikipedia.org/wiki/Plasma_gun
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The [b]charged bank of electrical capacitors (also called a Marx bank or Marx generator) is switched onto the anode.[b] The gas breaks down. [b]A rapidly rising electric current flows across the backwall electrical insulator,[b] axisymmetrically, as depicted by the path (labeled 1) as shown in the Fig 1. The axisymmetric sheath of plasma current lifts off the insulator [b]due to the interaction of the current with its own magnetic field (J×B force).[b] The plasma sheath is accelerated axially, to position 2, and then to position 3, ending the axial phase of the device.
The whole process proceeds at many times the speed of sound in the ambient gas. As the current sheath continues to move axially, the portion in contact with the anode slides across the face of the anode, axisymmetrically. When the imploding front of the shock wave coalesces onto the axis, a reflected shock front emanates from the axis until it meets the driving current sheath which then forms the axisymmetric boundary of the 'pinched' or focused hot plasma column.
Notice the way it works Nereid? It uses *electricity* to accelerate charged particles. That in no way lends any support to "magnetic reconnection" being a unique form of energy release.
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The plasma penetrates the barrier and enters the transverse field region. While doing so it generates waves in the lower hybrid frequency range.
Waves at lower hybrid frequencies have also been measured on the inside of the magnetopause by the Cluster spacecraft.
That's called *induction". It has absolutely nothing whatsoever to do with "magnetic reconnection". Both your transmission end *and* your receiving end of this energy transfer process involves the use of electricity to accelerate charged particles, and this kinetic movement is turned back into electrical current at the receiving end. How in the world can any such experiment by used to justify "magnetic reconnection" as any sort of unique energy release mechanism?
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The objective of this project is to study how the ion gyro radius affects the experimental results. The plasma gun that was used in the experiments at KTH has been moved to West Virginia University where, at present, it is being reassembled and and modernised. The experimentalist is expected to make characterising measurements of the penetration across the magnetic barrier for plasmas with different ion species. The different species have different mass, and hence the ion gyro radius will differ. In this way the influence of the ion gyro radius on the penetration process can be assessed.
In other words, bigger atoms generate more electrical induction in the plasma at the receiving end. Big deal. This whole experimental approach does nothing at all to demonstrated "magnetic reconnection' is a unique form of energy transfer. Nothing about a plasma gun supports the idea that "magnetic reconnection" can accelerate ions, and nothing about induction in double layers supports "magnetic reconnection" as a unique form of energy. The whole thing is related to the use of electrical current to generate kinetic energy, which is then turned back into current at the receiving end, generating auroral currents in the Earth's atmosphere. In no possible way could this type of experiment ever be used to support "magnetic reconnection" as a unique form of energy transfer.
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The project is carried out at West Virginia University (WVU) in the USA.
It sounds suspiciously like a political pork barrel spending program if you ask me.
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Research leader and scientific advisor at WVU is Dr. Herbert Gunell.
Perhaps you could get Dr. Herbert Gunell to explain to us exactly which phase of this plasma gun energy transfer process represents a unique form of energy that is attributable to "magnetic reconnection"? I see absolutely nothing about this experimental idea that even remotely resembles a unique form of energy transfer. All I can see in this experiment is electrical current being used to accelerate charged particles and charged particles generating induction based electrical currents once the fast moving particles run into a stationary electromagnetic field at the other end. Nothing about this energy transfer process even remotely resembles a unique form of energy release, or energy transfer.
Unless you can explain to me why I would not expect to observe neutrino emissions from the high energy events in the solar atmosphere, I see no reason to believe that they do not occur there, or that I would not see surface related "hits" from such events. Lots of different kinds of high energy cosmic ray interactions might release neutrinos in the upper atmosphere of the sun. I could almost be logically certain to observe more than just a single point source of neutrinos from the sun's core.
Alas Michael, and I say this with genuine respect and kindness, the history of science is littered with faux pas based upon arguments of personal credulity. Unless your wording here is a mere literary device, that type of approach is not generally considered a convincing route to better definition of the physical world.
While all theories have some type of mental model within, the main virtue of their inner intellectual mechanics is to construct a framework for *quantitative* prediction. A terrific example is Tycho Brahe who was one of the first to suggest and enact our 'modern' program - to measure some phenomena to the best accuracy available, in order to then present a body of data as a benchmark for comparison of any candidate models that are presented as purporting to explain said phenomena.
A large slab of both theoretical and observational effort is devoted to 'radii of variation' - for measurement we call this observational error ( various categories ), and similiarly for theory. But data has prime place, as it is the razor that slices off any errant models that lie outside the radius. So if newer concepts are to displace any currently well performing ones ( that are within the radius ), they have the burden ( under this modern program ) of equalling or bettering any incumbents. To me it appears that the criticism of EU ( and not of yourself as a person ) in this thread seems to relate to whether it compares favourably to existing quantitative knowledge. I don't know if EU does or does not, I'm just pointing out that there may be differing assumptions hereabouts as to what is a valid standard of proof to judge that.
It can be quite amazing what turns up sometimes:
Feynman's path integral method, a very exacting calculational machine in quantum electrodynamics ( & later generalised ) specifies that all possible alternate ( but unseen ) event sequences are summated. The result are probabilities, including a normalised denominator - a non-trivial exercise of itself. That then leads to very exact testable quantitative predictions. The measurement of the electron's magnetic moment ( ratio of it's dipole strength to angular momentum ) disagreed with the QED number only after the ninth decimal place! This is despite that we really have no everday gut-feeling clue as to what it really means by all possible alternates summating. ( Note that the integral is of the behaviour of virtual particles ie. 'existing' only to suit the model ). But an arrow that accurate is going to be kept however weird it seems.
[snip]
Your comment MikeH may be juxtaposed with this, from one of Michael's posts:
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It [the universe] doesn't care about math either. It does it's thing in it's own way, irrespective of what mathematical presentations we make on paper.
While rather heavy, Quantum Theory and Relativity, by Arthur Jaffe, a recent review, struck me as highly pertinent (the link is to a PDF).
In particular, re the electron's magnetic moment:
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This non-linear field theory gave rise to rules of calculation in perturbation theory. One computed that the electromagnetic field interacted with and modified the magnetic moment of the electron. In 1947 Kusch, working at Columbia University, measured the change in the magnetic moment. It agreed precisely with the calculated effect that is first-order in the square of the electric
charge, namely
μKusch = κμDirac , where κ = 1.001 . (II.3)
This tiny increase of only 0.1 percent compared with the Dirac value could be measured, and ever since one puts great credence in quantum field theory.
Over the intervening years, the measurements of μ and other related quantities has been refined by many persons, especially Dehmelt and his student Gabrielse. Likewise the calculations have undergone enormous progress. In order to take the accuracy to terms proportional to e4, one required enormous computer power just to simplify the algebra required to multiply 4 × 4 matrices and calculate the relevant traces, much less compute the many integrals of rational functions Feynman diagrams). A great expert who carried out much of the theoretical work is T. Kinoshita.
On this 60th-anniversary of the 1947 measurement, one can test the value of μ to unbelievable accuracy. The latest result, see [43, 15], cited by the American Institute of Physics as the “outstanding physics achievement of 2006,� gives
The calculations and theory agree completely to this extent. And the accuracy of this test astounds the human mind.
(That's 12 decimal places MikeH, and no disagreement).
Then there's the General Theory of Relativity (GR).
What would Birkeland, let alone Newton or Archimedes, have made of (a loudspeaker, a dab of radioactive iron, a transparent crystal, and a tower) and (the brightening then fading of a completely unremarkable, if very faint, star, followed six years later by finding the star had become two stars, one red and one blue)? We need to assume that we could somehow explain everything in each bracket to all three ancient worthies, except for the tower and (for Birkeland) the loudspeaker*.
What possible connection could there be between these two sets of things?
The first sketches the famous Pound-Rebka experiment; the second the gravitational lensing of a Large Magellanic Cloud (blue) star by a 'local' red dwarf star. The connection between the two is GR - the first is a landmark terrestrial experimental verification of GR; the second an application of GR to estimate the mass of an isolated star.
Keep in mind that the only physical data we have to work with is some time-ordered outputs from some gadgets attached to telescopes; only our assumptions about the (mathematically expressed) relationship between 'reality' and (mathematically expressed) physics theories lets us blithely talk about 'detecting photons'.
The universe may not care about math ... but it sure seems to behave as if it does, to a mind-boggling degree.
* the techniques involved in obtaining even images of the star(s), let alone spectra, would be quite unknown to all, except for the 'Newtonian' telescope design!
Ok, but you missed a step as it relates to "magnetic reconnection". This is what concerns me about "modern" astronomers. They seem to think that they can derive information about the forces of nature from *uncontrolled* observations. That is *not* how science works. If one intends to show that there is a unique energy release mechanism called "magnetic reconnection", one must demonstrate that "magnetic reconnection" is a unique form of energy release that is not related to electrical current flows that "reconnect" inside plasma. The only way one could do that is in a lab using *control mechanisms". *If* one can demonstrate that "magnetic reconnection" isn't a figment of collective imagination, *then* one can look at the THEMIS data and try to do some comparisons of the THEMIS data between Alfven's ideas, and your new lab measurements of "magnetic reconnection". Simply pointing to an uncontrolled observation will not demonstrate that validity of any theory, not Alfven's theories, or your own. Simply pointing to the observation and claiming it is consistent with "magnetic reconnection" is absurd, because no one can even explain what is unique about "magnetic reconnection" in the first place, and the author of MHD theory called the idea nonsense. More importantly, magnetic fields have been studied in a lab over and over again, and they never "reconnection" in any controlled test on earth.
[snip]
It seems I have not done a good job of communicating what I meant; let me try again.
The 23 March, 2007 data from THEMIS seems to have been the trigger for the NASA PR, a link to which you posted on New Year's Day.
That PR uses the term "magnetic rope"; however, the abstract of what seems to be most pertinent AGU meeting presentation doesn't (perhaps the full presentation, and eventually the paper, will; sadly, we have neither available to us to check).
Neither PR nor the part of the AGU presentation abstract that refers to the 23 March event mentions 'magnetic reconnection'.
To repeat: the part of my post that you are quoting does not mention 'magnetic reconnection', nor does the the NASA PR, nor does the part of the AGU abstract that refers to the 23 March event(s).
I trust that this clarifies what I said, and if you don't mind, I'd like to get back to discussing how the Sun shines.
To do that, perhaps you would be patient enough to walk through how the THEMIS data (and the POLAR data, and the FAST data) - as reported in the AGU meeting presentation (not the NASA PR) - is consistent with the 'EU theory' explanation/account of how the Sun shines?
I guess there are levels of credulity depending on the stage/progress to date. I really wanted to find out whether you like the general sense of logical positivism or not. It isn't a panacea for all questions by any means, as some of the best ones are well outside it! But a scientific discussion with hidden and mixed assumptions can be a bit of a wally.... :-)
Agreed. I often think the same thing about "magnetic reconnection" theory. It seems to presume that magnetic fields of a massive magnitude can exist in extremely light plasma in the absence of current flow, and that magnetic fields have been shown to make and break connections. That seems like quite a wally to me. :)
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Heck, while General Relativity can be summarised by a single tensor equation, solving it is another task again! I do get a bit annoyed when it's implicit depedencies ( aka horrible & non-linear ) are glossed over in describing it. The solutions which have given excellent fruit are in the weak field area ( Mercury's perihelion, Taylor-Hulse pulsar, 1919 eclipse .... ). It's a good start for sure, with no other serious competitor, but the numerical relativity groups are having a real wrestle with the close-in/high-mass scenarios.
I hear you. Life tends to be a lot more complicated than it seems at first glance.
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Sounds like Edison, as he went through ~ 2000 materials in filament testing. I think one was grass! If I remember rightly he's the origin of the '1% inspiration, 99% perspiration' formula for genius. Personally I prefer the Woody Allen approach - '85% of success is just turning up' ! :-)
It seems to me that Birkeland certainly approached his experiments in the standard scientific manner, with a standard scientific intent. He obviously was trying to producing useful mathematical models that could be applied to real life observations using control mechanisms to see how different variable would affect his experiments. He was certainly interested in quantifying astronomical observations based on what he learned by tinkering with the control variables and then "guessing" at how them might apply to what he could observe in space. He seems like he was the quintessential scientist to me. Of course he didn't have the benefits of in situ measurements to then use to fine tune his theories, but he did try to quantify what he saw in space based on what he learned in his lab.
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Now there's an important fork in the road. One often unstated assumption is that physical 'laws' hereabouts ( in space and time ) are sufficiently similiar to distant space/time rules. Not a bad assumption, indeed it is the simplest option to choose.
Well, we will have to make some assumptions along the way no matter which fork in the road we choose. It seems logical to assume that plasma physics here on Earth is not really different than plasma physics anywhere else. The basic premises of EU theory are derived from the basic properties of plasma. We all seem to expect to find plasma pretty much everywhere in spacetime. There are scaling aspects to plasma physical oriented theories (or any theory) that may not ever be "lab tested", but the basic principles of plasma cosmology come from the basic properties of plasma and how it behaves in controlled laboratory conditions. I'd have to say that's probably the best we can hope to do with any theory that attempts to define the behaviors of a universe that is mostly made of plasma. I agree that we will have to make some assumptions along the way, but I don't see any way of avoiding that particular pitfall no matter which forks we choose.
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The dark matter issue began as an observation of only mildly reducing tangential velocities of stars with respect to the radial distance from galactic centres. The visible mass in the galaxy predicts a more Keplerian distribution. In our own solar system Newton/Kepler/Galileo give the radius-cubed/period-squared relation - and a more rapidly diminishing tangential velocity curve for those galaxies. The extreme version of the fork is: keep Newton et al but add dark matter, OR keep the observed mass but change gravity theory for that scale ( MOND ... ). ( GR is sufficiently close to Newton for these purposes here - weak field again ).
Yet there isn't really an obvious way to determine the validity of MOND theory vs. "dark matter" theory or EU theory based on only the movement patterns of a galaxies. The lensing aspects of these observations however does at least offer us another possible mechanism to distinguish between these various theories. Dark matter theories have been around as long as I can remember and were mentioned even when I was in college. MACHO types of DM theories seem quite viable to me personally, but I have never seen any empirical evidence that non baryonic forms of dark matter exist in nature, with the exception of neutrinos. Because we can empirically demonstrate that baryonic forms of mass, and neutrinos exist in nature, I can't really complain much when these ideas are put into a mathematical presentation. It's only when people start talking about WIMP and SUSY theory related particles that I tend to cry fowl. There is a need IMO to empirically demonstrate such forms of matter before trying to claim they have some effect on nature.
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This idea seem very logical to me until someone begins to insert placeholder terms into the mathematics to "explain" particular observations. Then the placeholder terms become suspect, and the mathematics becomes even more suspect. If we observe the acceleration of objects like solar wind particle or galaxies, is it scientifically acceptable to chalk up this acceleration to something that cannot be demonstrated to exist in nature? What if there are other forces of nature that might this acceleration process in plasma? This is where the "quantification only" approach to science has broken down as it relates to astronomy and astronomy theory IMO. While the basic idea is a noble one, in practical application in astronomy it has been abused by metaphysical constructs that have crept into the mathematical models.
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Yes, indeed. Point well made. Dark energy is such a place-holder. I saw another derivation of it a few weeks ago. I felt like asking what does a negative pressure in outer space really mean guys?
Exactly. That's exactly the right question IMO as well.
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The term in the equation which represents it *analogises* to our everyday meaning for sure, but it's presence there flips the sign of a gravitational energy term and then ..... expand away Mr. Universe. I guess there's a phenomenology/numerology approach here, but it would help us lesser mortals who are eavesdropping if that type of thinking was highlighted as being such.
Now I'd feel a lot better if someone could show that "dark energy" actually exists and has some effect on nature in a controlled experiment. I an explain the acceleration of mostly plasma and iron objects with EM fields. I don't need any exotic forms of energy to explain why objects might accelerate. I can see how EM fields could "flip the sign" of the gravitational energy too. I just don't see any way to validate the notion that dark energy has anything at all to do with making objects expand or accelerate. It may look mathematically elegant, but without some empirical confirmation, it's difficult then to compare this metaphysical idea to any other idea in an objective manner.
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Inflationary theory has a similiar feel. A superluminal exponential expansion of spacetime flattens metrics, and separates the universe into causally disconnected regions ( which are now coming back within horizons ) thus freezing in homogenous features that we see now in the CMB. A terrific bit of work but we could leave out the 'face of God' stuff when variations from uniformity only appear four magnitudes down!
My "beef" with inflation is exactly pretty much the same as it is for dark matter. It's never been shown to actually exist in nature, and no other scalar or vector field that is known to exist in nature acts like inflation. No other field will retain near constant density over several exponential increases in volume. It is therefore impossible for me to judge the validity of a theory that relies upon a truly "supernatural" concept. If we're leaving out the face of God ideas, then we should be leaving out all supernatural ideas IMO.
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However careful spotters will note that we haven't got a pre-inflation comparison data set here, merely a set of deductions ( consistent, yes ) extrapolating backwards from ~ 300Kyrs post BB ( the CMB sphere ). Since we postulate both uniformity and opacity prior to that time does it really matter what the 'inflaton' particle was that slowly rolled off some potential field? It is not ( and theory says will not ) be now measurable outside of 'relic' data, as the energy scale is humungous compared to current levels.
Well, there's a more basic issue here to consider. While we can plot the basic concept of expansion backwards in time, we cannot be certain that all matter and all energy was ever collected to a "point". Finding even a "tiny relic" of inflation in a lab would make the idea seem less "supernatural", but without it, and without any real knowledge of what the universe looked like 13.7 billion years ago, I can't for life of me figure out a legitimate way to test this concept.
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Well I'd say you are in good company there! I think that, like Feynman dipping an O-ring into ice-water, we all like a handle on the universe that we can grab onto and yank ... :-)
I like scientists that roll up their sleeves and test their ideas in controlled ways. To me at least, that is what real science is all about. Now of course astronomy presents us with some serious challenges in the sense that we cannot "control" what goes on in space, but we can at least put control mechanisms and basic forces that relate to plasma to the test in a lab. While many idea in astronomy today cannot be tested, "magnetic reconnection" could and should be tested in controlled experiments.
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That's the both ends reaching to meet in the middle for sure, and generally we have the dichotomy of scientific labor into theory and experimentalist streams. Feynman once took a sabbatical into a bio-lab to get a break from his blackboard. Lisa Randall does an excellent job in her 'Warped Passages' book of illustrating this very point ... and others. ( It's a great all round book even if you have no formal background ).
I'll keep that book in mind the next time I'm looking for reading material. At the moment I'm reading a book by Anthony Peratt and it's a bit slow going for me personally. I suspect I'll be at it awhile.
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The overlapping of and the extension of domains of applicability is a difficult synthetic process. Alas such 'sewing' is neither quite opposite, nor orthogonal, to reductionist inquisitions.
Indeed. I agree. I just like the "hands on" approach to science, because that is what I was taught in school and I was taught it applied to all realms of science. I can see that there are special problems in astronomy that don't apply to say electrical engineering, but most if not all aspects of Birkelands ideas were lab tested before he ever formally proposed them. That seems like a good step in the right direction.
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It was a bothersome divergence in the summation I described earlier, which yielded infinites close in to the electron for QED. So by 'moving' within the cloud of virtual particles the coupling ( ~ strength of interaction, ~ probability of a vertex occurring ) increased. More and more of the previously ignored higher order terms ( diagrams ) dominated, these had been given upper bounds before that couldn't now apply. Feynman's solution was a simple fiat, subtract away the said infinity. So that yields : 'bare' charge + masking from a virtual cloud = observed charge. So if higher kinetic energies bring you closer in to an electron it won't be as per Coulomb. I think this is weird.
I think it's weird too, and Chapman probably did too. Unfortunately we can't rule out ideas because they are "weird" to our conscious mind, which goes back to your first point as well. We also can't be sure something is going to happen because is "seems" logical. That is why the testing of even weird ideas is so very important.
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Fair enough, let us await with interest.
It has certainly peaked my interest. :)
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Yup, I follow you there. See as above. One thing harder than hidden assumptions, is hidden circular arguments. This can of course depend upon the precision of language and care with definitions too.
I agree with that point 100 percent.
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Try this : Galileo/Newton give inertia as a material property with frames defining forces as those influences which cause deviations from straight lines. Einstein gives straight lines devolving to those paths which light travels along ( SR or GR ). Now in cosmology a frequently used yardstick is 'co-moving distance', with a factor/ratio that scales 'real' distances to some co-ordinate system choice. But hang on, haven't we used some light ( path/speed ) type simultaneity program to lay out a grid in space to quantify our measurements? This *empirical* frame can't be BOTH the 'real distance' AND the co-ordinate frame! So choose it as representing one of them, and you will then leave the other as a pure abstraction. Expansion of space then is one-half mathematics only. The trouble is an old unresolved chestnut which is whether 'space' is defined by 'matter' or vice-versa. Yes GR connects the two but avoids nailing either. Similiarly Mach worried the hell out of the 'inertia' bit - see Newton's pail of water - and 'modern' resolution seems to involve the as yet unseen Higgs particle....
That was an interesting way to explain it. I appreciate that explanation. It does demonstrate the difficult nature of figuring out "reality" and how reality functions. Our own assumptions and arguments can easily lead us astray.
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I've never understood the term 'magnetic reconnection'. :-(
Me either. I think that is because nobody has ever actually defined the physical energy release process that is unique to "magnetic reconnection" and no self respecting electrical engineer talks about magnetic fields making and breaking connections. More importantly no one has ever demonstrated that "magnetic reconnection" works in a lab. In this particular instance, that is unacceptable. There is absolutely no scientific reason this idea should not be put to a test. I the father of MHD theory doesn't buy the idea, then I'll need to see some evidence that it exists and has the effects it claims to have on plasma. I see nothing from controlled testing that leads me to believe that magnetic reconnection occurs in nature. That's a *big* problem IMO.
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Please don't forget all the min-suns that the particle physicists make as they do have relevance to plasmas. Have you read any of Terry Pratchett's Discworld books? If not, I implore you to do so, I reckon you'll love what goes on on in the High Energy Magic building. :-)
No, I've not read his books yet. Your enthusiasm is so noted. Terry's book sounds more interesting to me personally so that book will go to the top of my "to read" list. :)
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String theory currently has an embarrassment of riches, with no principle(s) to trim down the flock. There's a wide panoply of variants for those little curled up dimensions, the Calabi-Yau spaces. Their behaviour ( in theory ) gives our forces and fields in detail. Quantity yes, precision no.
Well, I'm definitely not a believer in string theory, so I have to agree with you on this point.
While rather heavy, Quantum Theory and Relativity, by Arthur Jaffe, a recent review, struck me as highly pertinent (the link is to a PDF).
Thanks for that link, I'll have a crack at it.. :-)
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In particular, re the electron's magnetic moment:
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This non-linear field theory gave rise to rules of calculation in perturbation theory.........
μ = κ60 μDirac , where κ60 = 1.001 159 652 180 85(±76) . (II.4)
The calculations and theory agree completely to this extent. And the accuracy of this test astounds the human mind.
(That's 12 decimal places MikeH, and no disagreement).
Nice one! :-) I was recalling a late 1970's lecture by Feynman, so it's been drilled down even further since.
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Keep in mind that the only physical data we have to work with is some time-ordered outputs from some gadgets attached to telescopes; only our assumptions about the (mathematically expressed) relationship between 'reality' and (mathematically expressed) physics theories lets us blithely talk about 'detecting photons'.
This deserves a quote from Lisa Randall ( Warped Passages p9 ):
Quote:
As physics evolved in the twentieth century, it moved away from things that can be directly observed with the naked eye to things that can be "seen" only through measurements coupled with a theoretical train of logic.
I once heard a physicist use the phrase 'the electron abstraction', and when I queried that he asked if I'd ever seen one. He was predominantly an experimenter and made me focus on the whole shebang of measurement. He didn't really disbelieve in electrons. He was teaching us to be sure as we can about what we think we are detecting. While dear Schroedinger's cat gets killed ( recurrently, it would seem! ) by an alpha particle triggered event sequence that climbs up the distance scales - for which entity did you put a saucer of milk down? The high energy physics ( terrestrial colliders ) program has been terrific in resolving smaller scale detail. But like repeatedly blowing up houses to count doorknob fragments I get a feeling we are missing some important subtler issues - like whether you twist the knob to the left or right to open the bathroom door. Alas we can't do an Alice ( or an Edwin Abbott ) and vary our personal sensory granularity to suit. So we have to make do with effective ( scale dependent ) theories.
The really weird thing is that sometimes the math is well ahead of us. The neutrino was proposed long before it's discovery, due to energy budgets not agreeing. The positron likewise, as it popped out as an alternate solution to Dirac's QM treatment of the electron. Also Gelmann's 'eight-fold way' tamed the particle zoo and preceeded actual detection of the hard sub-nucleon-size mass concentrations we now call quarks. Oh, and not to forget Uranus and Neptune being emitted ( with some luck too ) by the numerical orreries of classical celestial mechanics. Penrose has a lot to say on this area. ( I am on my third attempt at plowing into 'The Road To Reality' ).
Cheers, Mike.
( edit ) NB Gell-Mann
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I've seen many folks claim to be smarter than Einstein (Lambda proponents) and yet they can't produce any empirical evidence that "dark energy" has any effect on matter or space or spacetime or anything in a controlled scientific test.
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It may look mathematically elegant, but without some empirical confirmation, it's difficult then to compare this metaphysical idea to any other idea in an objective manner.
I have already asked Michael several questions concerning the consistency between these 'no shades of grey' statements and his (apparent) explicit endorsement of hypotheses which incorporate, at their core, ideas which seem to be coloured deepest grey.
Here I would like to engage in a preliminary exploration of the (for now loosely worded) hypothesis that MM applies his oft-stated fundamental criterion in a very selective way, to wit: it is applied exclusively to 'non-baryonic dark matter', 'dark energy', and 'inflation'.
To test this hypothesis, I shall use as input all MM posts in this thread, to date, as they relate to MOND.
At the outset, I should note that the test *assumes* that MM is well aware that all internally consistent MOND proposals, published to date^, cannot be empirically tested, under controlled conditions, anywhere closer than ~10kpc from the solar system, even in principle. Of course, should independently verifiable, objective evidence emerge that MM was not, before now, aware of this central feature of such MOND proposals, the test (below) becomes moot.
There are, I think, four substantive statements, by MM, on MOND, in this thread:
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I actually do entertain MOND type theories, but I personally tend to suspect that the "missing mass" is located inside mostly Iron and Nickel suns.
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I personally tend to favor "MACHO" oriented "dark matter" explanations for these observations, but IMO it is premature to rule out MOND theory at this time. Some of these observations are quite new and require some time to work though when it comes to explaining these events from a modified gravity perspective.
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It therefore becomes very difficult to judge the validity or merit of many of the non empirically demonstrated aspects of Lambda-CDM theories in relationship to other theories, including EU theories and MOND theories, MECO theories, ect.
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Yet there isn't really an obvious way to determine the validity of MOND theory vs. "dark matter" theory or EU theory based on only the movement patterns of a galaxies. The lensing aspects of these observations however does at least offer us another possible mechanism to distinguish between these various theories. Dark matter theories have been around as long as I can remember and were mentioned even when I was in college. MACHO types of DM theories seem quite viable to me personally, but I have never seen any empirical evidence that non baryonic forms of dark matter exist in nature, with the exception of neutrinos. Because we can empirically demonstrate that baryonic forms of mass, and neutrinos exist in nature, I can't really complain much when these ideas are put into a mathematical presentation. It's only when people start talking about WIMP and SUSY theory related particles that I tend to cry fowl. There is a need IMO to empirically demonstrate such forms of matter before trying to claim they have some effect on nature.
In addition there is this:
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Well, this is where my primary criticism of standard theory comes from. Without any control mechanism, a pure observation cannot in and of itself tell us the actual 'cause' of that observation. In other words, if we see objects in an apparent spurt of acceleration, unless we can demonstrate that our proposed solution exists in controlled empirical ways, it is impossible to verify or falsify any quantification presented. In other words I might present you with a calculation of acceleration based on a "magic force". Simply by looking at the observation of acceleration, I cannot rule out "magic force" as the cause of that acceleration. I can't rule it in either. Only a controlled test could rule it in.
While this does not, explicitly, mention MOND, there can surely be no doubt that "magic force" fits MOND perfectly - it's an ad hoc, arbitrary modification of Newtonian gravity; as a "proposed solution", we cannot "demonstrate that [it] exists in controlled empirical ways"; and so on.
Note too that MM states - unequivocally - that this is "where my primary criticism of standard theory comes from".
It would thus seem, based on the empirical evidence, presented above, that the (admittedly loosely-worded) hypothesis is:
Keep in mind that the only physical data we have to work with is some time-ordered outputs from some gadgets attached to telescopes; only our assumptions about the (mathematically expressed) relationship between 'reality' and (mathematically expressed) physics theories lets us blithely talk about 'detecting photons'.
This deserves a quote from Lisa Randall ( Warped Passages p9 ):
Quote:
As physics evolved in the twentieth century, it moved away from things that can be directly observed with the naked eye to things that can be "seen" only through measurements coupled with a theoretical train of logic.
I once heard a physicist use the phrase 'the electron abstraction', and when I queried that he asked if I'd ever seen one. He was predominantly an experimenter and made me focus on the whole shebang of measurement. He didn't really disbelieve in electrons. He was teaching us to be sure as we can about what we think we are detecting. While dear Schroedinger's cat gets killed ( recurrently, it would seem! ) by an alpha particle triggered event sequence that climbs up the distance scales - for which entity did you put a saucer of milk down? The high energy physics ( terrestrial colliders ) program has been terrific in resolving smaller scale detail. But like repeatedly blowing up houses to count doorknob fragments I get a feeling we are missing some important subtler issues - like whether you twist the knob to the left or right to open the bathroom door. Alas we can't do an Alice ( or an Edwin Abbott ) and vary our personal sensory granularity to suit. So we have to make do with effective ( scale dependent ) theories.
Thanks MikeH! :-)
In other fora, I've been banging on about this for quite some time, and while I've read Randall's book (more than once actually), I missed that gem; thanks.
One aspect that attracts me to Einstein@Home (and LIGO and GW detectors in general) is the imminent possibility of having another, non-electromagnetic, window on the universe beyond our solar system. And equally fascinating is the possibility of iron-clad null results, with all that will entail for GR.
Even better: already one new window is, very slightly ajar - ultra-high energy cosmic rays ... and a third should open within the next decade - neutrino astronomy.
The 'we observe the universe only through the filter of theory' is doubly applicable to astronomy (beyond the solar system) - no Earthly lab will ever be able to do controlled experiments on an object with a mass of a few million sols and a radius of < 100,000 km (for those who may miss this, that's a not-too-inaccurate description of something astronomers call SgrA*), for example, and we only know of the existence of such objects via a doubly lengthy chain of theory-laden measurements.
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The really weird thing is that sometimes the math is well ahead of us. The neutrino was proposed long before it's discovery, due to energy budgets not agreeing. The positron likewise, as it popped out as an alternate solution to Dirac's QM treatment of the electron. Also Gelmann's 'eight-fold way' tamed the particle zoo and preceeded actual detection of the hard sub-nucleon-size mass concentrations we now call quarks. Oh, and not to forget Uranus and Neptune being emitted ( with some luck too ) by the numerical orreries of classical celestial mechanics. Penrose has a lot to say on this area. ( I am on my third attempt at plowing into 'The Road To Reality' ).
Cheers, Mike.
IIRC, Gell-Mann himself didn't intend quarks to be 'real' but rather a very neat application of math that merely *described* the behaviour of (real) protons, neutrons, pi mesons, etc!
To your list I think you might add the experiments which tested the EPR paradox - the (math-based) predictions preceded the experiments by decades, for all the deeply discomforting implications of a 'QM 1, Einstein 0' result.
It's also very easy to overlook the hundreds and hundreds of 'downstream' particle discoveries, which flowed from the Standard Model ... Psi/J get star billing (because it was the first), but it's so easy to forget that even one 'blank cell' in the huge table would have caused a great deal of head-scratching. My personal favourite is the tau neutrino, alongside the determination of the width of the Z (or was it the W?), which thus ruled out any other, 'light', 'non-sterile' neutrinos.
It seems I have not done a good job of communicating what I meant; let me try again.
The 23 March, 2007 data from THEMIS seems to have been the trigger for the NASA PR, a link to which you posted on New Year's Day.
That PR uses the term "magnetic rope"; however, the abstract of what seems to be most pertinent AGU meeting presentation doesn't (perhaps the full presentation, and eventually the paper, will; sadly, we have neither available to us to check).
Well, let's look at the verbiage they did use in the press release:
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A magnetic rope is a twisted bundle of magnetic fields organized much like the twisted hemp of a mariner's rope. Spacecraft have detected hints of these ropes before, but a single spacecraft was insufficient to map their 3D structure. THEMIS' five identical micro-satellites were able to perform the feat.
That sure sounds like Alfven's description of a magnetic rope to me.
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THEMIS also has observed a number of small explosions in Earth's magnetic bow shock. "The bow shock is like the bow wave in front of a boat," explained Sibeck. "It is where the solar wind first feels the effects of Earth's magnetic field. Sometimes a burst of electrical current within the solar wind will hit the bow shock and—Bang! We get an explosion."
Bangs from electrical currents in the solar wind Nereid? How can you simply ignore the implications of this statement? It's an *electric* universe Nereid. Even our friends at NASA are noting this fact. Are you going to just ignore this data or what?
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Neither PR nor the part of the AGU presentation abstract that refers to the 23 March event mentions 'magnetic reconnection'.
No, but you claimed that we were studying "magnetic reconnection" with in-situ measurements!
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Pace Michael, it seems 'magnetic reconnection' is not only part of modern space science, but is being studied in situ (and quantitatively).
That statement is ridiculous Nereid. We can't "study" something from space in uncontrolled observations. We could only hope to demonstrate that Alfven was incorrect about "magnetic reconnection" in a lab, we could never do so in pure observations from space. You can't even explain what is unique about "magnetic reconnection" energy releases, and therefore it is absolutely impossible to you to study it in space or in a lab.
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Is there a reason - good or not - why 'magnetic rope' is not mentioned in the abstract?
Is there a reason that you personally need to deny what they said in their press releases? Are you hoping these field aligned currents are something other than a 'magnetic ropes'? What else is going to form those twisted rope structures in light plasma, transfer that much energy through light plasma, and create those "bangs" they were talking about?
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To repeat: the part of my post that you are quoting does not mention 'magnetic reconnection', nor does the the NASA PR, nor does the part of the AGU abstract that refers to the 23 March event(s).
I'm directly questioning your personal statement about how we were "studying" magnetic reconnection. NASA press release said absolutely nothing that I could find fault with. They even talked about the electrical currents in the solar wind. NASA seems to be openly discussing the electrical currents in space, whereas you continue to deny it's role in astronomy. If you aren't careful Nereid, you'll be the last individual on the planet to notice what everyone else has already noticed. The universe is electric. Evidently the universe itself is 'against the mainstream' too. I guess you'll just have to ban the whole universe from BAUT. ;)
It seems I have not done a good job of communicating what I meant; let me try again.
The 23 March, 2007 data from THEMIS seems to have been the trigger for the NASA PR, a link to which you posted on New Year's Day.
That PR uses the term "magnetic rope"; however, the abstract of what seems to be most pertinent AGU meeting presentation doesn't (perhaps the full presentation, and eventually the paper, will; sadly, we have neither available to us to check).
Well, let's look at the verbiage they did use in the press release:
Quote:
A magnetic rope is a twisted bundle of magnetic fields organized much like the twisted hemp of a mariner's rope. Spacecraft have detected hints of these ropes before, but a single spacecraft was insufficient to map their 3D structure. THEMIS' five identical micro-satellites were able to perform the feat.
That sure sounds like Alfven's description of a magnetic rope to me.
Quote:
THEMIS also has observed a number of small explosions in Earth's magnetic bow shock. "The bow shock is like the bow wave in front of a boat," explained Sibeck. "It is where the solar wind first feels the effects of Earth's magnetic field. Sometimes a burst of electrical current within the solar wind will hit the bow shock and—Bang! We get an explosion."
Bangs from electrical currents in the solar wind Nereid? How can you simply ignore the implications of this statement? It's an *electric* universe Nereid. Even our friends at NASA are noting this fact. Are you going to just ignore this data or what?
Quote:
Neither PR nor the part of the AGU presentation abstract that refers to the 23 March event mentions 'magnetic reconnection'.
No, but you claimed that we were studying "magnetic reconnection" with in-situ measurements!
Quote:
Pace Michael, it seems 'magnetic reconnection' is not only part of modern space science, but is being studied in situ (and quantitatively).
That statement is ridiculous Nereid. We can't "study" something from space in uncontrolled observations. We could only hope to demonstrate that Alfven was incorrect about "magnetic reconnection" in a lab, we could never do so in pure observations from space. You can't even explain what is unique about "magnetic reconnection" energy releases, and therefore it is absolutely impossible to you to study it in space or in a lab.
Quote:
Is there a reason - good or not - why 'magnetic rope' is not mentioned in the abstract?
Is there a reason that you personally need to deny what they said in their press releases? Are you hoping these field aligned currents are something other than a 'magnetic ropes'? What else is going to form those twisted rope structures in light plasma, transfer that much energy through light plasma, and create those "bangs" they were talking about?
Quote:
To repeat: the part of my post that you are quoting does not mention 'magnetic reconnection', nor does the the NASA PR, nor does the part of the AGU abstract that refers to the 23 March event(s).
I'm directly questioning your personal statement about how we were "studying" magnetic reconnection. NASA press release said absolutely nothing that I could find fault with. They even talked about the electrical currents in the solar wind. NASA seems to be openly discussing the electrical currents in space, whereas you continue to deny it's role in astronomy. If you aren't careful Nereid, you'll be the last individual on the planet to notice what everyone else has already noticed. The universe is electric. Evidently the universe itself is 'against the mainstream' too. I guess you'll just have to ban the whole universe from BAUT. ;)
Professor Drake and his current focus on magnetic reconnection - “Key discoveries in magnetic reconnection made by Dr. Drake and his colleagues center around the role of whistler waves in driving and controlling magnetic reconnection. Traditionally it was believed that the Alfven wave played the key role in driving reconnection. At small scales, however, electron and ion motion decouple and the dynamics is controlled by whistler waves. �
Magentic reconnection - “Magnetic reconnection is a phenomenon which is of particular importance in solar system plasmas. In the solar corona, it results in the rapid release to the plasma of energy stored in the large-scale structure of the coronal magnetic field, an effect which is thought to give rise to solar flares. Small scale reconnection may play a role in heating the corona, and, thereby, driving the outflow of the solar wind. In the Earth's magnetosphere, magnetic reconnection in the magnetotail is thought to be the precursor for auroral sub-storms....�
Mangetic reconnection region larger than 2.5 million km found in solar wind - “Using the ESA Cluster spacecraft and the NASA Wind and ACE satellites, a team of American and European scientists have discovered the largest jets of particles created between the Earth and the Sun by magnetic reconnection... �
Direct observation of 3D magnetic reconnection - “...multipoint measurements by the Cluster mission reveals, for the first time, a direct observation of a 3D magnetic field topology at the magnetopause, resulting from magnetic reconnection at multiple sites...�
I dunno Michael, biggest cosmological mystery to me right now is how anyone can say the universe is electric instead of electromagnetic....
And here's another example of a solar model, and not just some observations and educated guesses. If you indeed had a working solar model, then it would be possible to show how it's equivalent to the standard one, because the standard one works, and is successful at reproducing observations over the course of a star's lifetime, as well as producing scenarios of stellar interiors that agree with both standard physics *and* subsequent measurements, so then by comparing the variables in your model to those in the standard one, it would be possible to make great strides, I would think....
Standard Solar Model
Please pay particular attention to Fig. 3, showing that “most stellar energy production occurs in the core.� (Too bad there is no other model [that I'm aware of] showing that most energy can be produced in any other region other than the core, but then there's a lot of physics to consider besides electricity....)
(my
)
(my bold)
One of the THEMIS-related presentations at the AGU meeting is OpenGGCM Simulation of the March 23, 2007 Substorm Observed by THEMIS:
What is "OpenGGCM"?
The Open Geospace General Circulation Model is:
Are you familiar with this, Michael?
It would seem that it aims to model the observable behaviour of the Earth's magnetosphere - just what Birkeland set out to do* - based on contemporary plasma physics (which, of course, owes much to Alfvén and MHD, but also extends it, to take account of discoveries and developments after Alfvén ceased his scientific career).
Its outputs are:
There's a paper by Ping Zhu on that website that you might find particularly interesting Michael ("Multiscale MHD Modelings of Substorm Onset in Earth's Magnetotail").
Would you mind taking a look at some of this material (including the code, if you're interested; it's open source), and commenting on the extent to which you feel it incorporates the 'right' parts of Birkeland's work? Also, if you feel any of the underlying physics is not 'qualified', would you mind outlining what, and why you feel it isn't?
* though, of course, he didn't know anything about the distinction between the magnetosphere and the IPM; nonetheless, all the astronomical and geophysical observables he sought to explain and model relate directly to the magnetosphere (except for visual waveband observations of the Sun, including the corona)
RE: RE: Indeed ... and so
)
Perhaps you could get Dr. Herbert Gunell to explain to us exactly which phase of this plasma gun energy transfer process represents a unique form of energy that is attributable to "magnetic reconnection"? I see absolutely nothing about this experimental idea that even remotely resembles a unique form of energy transfer. All I can see in this experiment is electrical current being used to accelerate charged particles and charged particles generating induction based electrical currents once the fast moving particles run into a stationary electromagnetic field at the other end. Nothing about this energy transfer process even remotely resembles a unique form of energy release, or energy transfer.
It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland
RE: RE: Unless you can
)
Your comment MikeH may be juxtaposed with this, from one of Michael's posts:
While rather heavy, Quantum Theory and Relativity, by Arthur Jaffe, a recent review, struck me as highly pertinent (the link is to a PDF).
In particular, re the electron's magnetic moment:
(That's 12 decimal places MikeH, and no disagreement).
Then there's the General Theory of Relativity (GR).
What would Birkeland, let alone Newton or Archimedes, have made of (a loudspeaker, a dab of radioactive iron, a transparent crystal, and a tower) and (the brightening then fading of a completely unremarkable, if very faint, star, followed six years later by finding the star had become two stars, one red and one blue)? We need to assume that we could somehow explain everything in each bracket to all three ancient worthies, except for the tower and (for Birkeland) the loudspeaker*.
What possible connection could there be between these two sets of things?
The first sketches the famous Pound-Rebka experiment; the second the gravitational lensing of a Large Magellanic Cloud (blue) star by a 'local' red dwarf star. The connection between the two is GR - the first is a landmark terrestrial experimental verification of GR; the second an application of GR to estimate the mass of an isolated star.
Keep in mind that the only physical data we have to work with is some time-ordered outputs from some gadgets attached to telescopes; only our assumptions about the (mathematically expressed) relationship between 'reality' and (mathematically expressed) physics theories lets us blithely talk about 'detecting photons'.
The universe may not care about math ... but it sure seems to behave as if it does, to a mind-boggling degree.
* the techniques involved in obtaining even images of the star(s), let alone spectra, would be quite unknown to all, except for the 'Newtonian' telescope design!
RE: RE: Indeed ... and so
)
It seems I have not done a good job of communicating what I meant; let me try again.
The 23 March, 2007 data from THEMIS seems to have been the trigger for the NASA PR, a link to which you posted on New Year's Day.
That PR uses the term "magnetic rope"; however, the abstract of what seems to be most pertinent AGU meeting presentation doesn't (perhaps the full presentation, and eventually the paper, will; sadly, we have neither available to us to check).
Neither PR nor the part of the AGU presentation abstract that refers to the 23 March event mentions 'magnetic reconnection'.
Is there a reason - good or not - why 'magnetic rope' is not mentioned in the abstract? Are the terms actually used ('substorms', 'a small storm', 'substorm sequences', 'particle injections and dipolarization signatures', 'Earthward flow pulse ahead of a predominantly duskward flow accompanied a strong field-aligned current pair signature', 'field aligned currents, arc and outflowing ions') merely extended descriptions of 'magnetic rope'? How do the terms actually used in the abstract relate to Alfvén's definition?
And so on.
To repeat: the part of my post that you are quoting does not mention 'magnetic reconnection', nor does the the NASA PR, nor does the part of the AGU abstract that refers to the 23 March event(s).
I trust that this clarifies what I said, and if you don't mind, I'd like to get back to discussing how the Sun shines.
To do that, perhaps you would be patient enough to walk through how the THEMIS data (and the POLAR data, and the FAST data) - as reported in the AGU meeting presentation (not the NASA PR) - is consistent with the 'EU theory' explanation/account of how the Sun shines?
RE: I guess there are
)
Agreed. I often think the same thing about "magnetic reconnection" theory. It seems to presume that magnetic fields of a massive magnitude can exist in extremely light plasma in the absence of current flow, and that magnetic fields have been shown to make and break connections. That seems like quite a wally to me. :)
I hear you. Life tends to be a lot more complicated than it seems at first glance.
It seems to me that Birkeland certainly approached his experiments in the standard scientific manner, with a standard scientific intent. He obviously was trying to producing useful mathematical models that could be applied to real life observations using control mechanisms to see how different variable would affect his experiments. He was certainly interested in quantifying astronomical observations based on what he learned by tinkering with the control variables and then "guessing" at how them might apply to what he could observe in space. He seems like he was the quintessential scientist to me. Of course he didn't have the benefits of in situ measurements to then use to fine tune his theories, but he did try to quantify what he saw in space based on what he learned in his lab.
Well, we will have to make some assumptions along the way no matter which fork in the road we choose. It seems logical to assume that plasma physics here on Earth is not really different than plasma physics anywhere else. The basic premises of EU theory are derived from the basic properties of plasma. We all seem to expect to find plasma pretty much everywhere in spacetime. There are scaling aspects to plasma physical oriented theories (or any theory) that may not ever be "lab tested", but the basic principles of plasma cosmology come from the basic properties of plasma and how it behaves in controlled laboratory conditions. I'd have to say that's probably the best we can hope to do with any theory that attempts to define the behaviors of a universe that is mostly made of plasma. I agree that we will have to make some assumptions along the way, but I don't see any way of avoiding that particular pitfall no matter which forks we choose.
Yet there isn't really an obvious way to determine the validity of MOND theory vs. "dark matter" theory or EU theory based on only the movement patterns of a galaxies. The lensing aspects of these observations however does at least offer us another possible mechanism to distinguish between these various theories. Dark matter theories have been around as long as I can remember and were mentioned even when I was in college. MACHO types of DM theories seem quite viable to me personally, but I have never seen any empirical evidence that non baryonic forms of dark matter exist in nature, with the exception of neutrinos. Because we can empirically demonstrate that baryonic forms of mass, and neutrinos exist in nature, I can't really complain much when these ideas are put into a mathematical presentation. It's only when people start talking about WIMP and SUSY theory related particles that I tend to cry fowl. There is a need IMO to empirically demonstrate such forms of matter before trying to claim they have some effect on nature.
Exactly. That's exactly the right question IMO as well.
Now I'd feel a lot better if someone could show that "dark energy" actually exists and has some effect on nature in a controlled experiment. I an explain the acceleration of mostly plasma and iron objects with EM fields. I don't need any exotic forms of energy to explain why objects might accelerate. I can see how EM fields could "flip the sign" of the gravitational energy too. I just don't see any way to validate the notion that dark energy has anything at all to do with making objects expand or accelerate. It may look mathematically elegant, but without some empirical confirmation, it's difficult then to compare this metaphysical idea to any other idea in an objective manner.
My "beef" with inflation is exactly pretty much the same as it is for dark matter. It's never been shown to actually exist in nature, and no other scalar or vector field that is known to exist in nature acts like inflation. No other field will retain near constant density over several exponential increases in volume. It is therefore impossible for me to judge the validity of a theory that relies upon a truly "supernatural" concept. If we're leaving out the face of God ideas, then we should be leaving out all supernatural ideas IMO.
Well, there's a more basic issue here to consider. While we can plot the basic concept of expansion backwards in time, we cannot be certain that all matter and all energy was ever collected to a "point". Finding even a "tiny relic" of inflation in a lab would make the idea seem less "supernatural", but without it, and without any real knowledge of what the universe looked like 13.7 billion years ago, I can't for life of me figure out a legitimate way to test this concept.
I like scientists that roll up their sleeves and test their ideas in controlled ways. To me at least, that is what real science is all about. Now of course astronomy presents us with some serious challenges in the sense that we cannot "control" what goes on in space, but we can at least put control mechanisms and basic forces that relate to plasma to the test in a lab. While many idea in astronomy today cannot be tested, "magnetic reconnection" could and should be tested in controlled experiments.
I'll keep that book in mind the next time I'm looking for reading material. At the moment I'm reading a book by Anthony Peratt and it's a bit slow going for me personally. I suspect I'll be at it awhile.
Indeed. I agree. I just like the "hands on" approach to science, because that is what I was taught in school and I was taught it applied to all realms of science. I can see that there are special problems in astronomy that don't apply to say electrical engineering, but most if not all aspects of Birkelands ideas were lab tested before he ever formally proposed them. That seems like a good step in the right direction.
I think it's weird too, and Chapman probably did too. Unfortunately we can't rule out ideas because they are "weird" to our conscious mind, which goes back to your first point as well. We also can't be sure something is going to happen because is "seems" logical. That is why the testing of even weird ideas is so very important.
It has certainly peaked my interest. :)
I agree with that point 100 percent.
That was an interesting way to explain it. I appreciate that explanation. It does demonstrate the difficult nature of figuring out "reality" and how reality functions. Our own assumptions and arguments can easily lead us astray.
Me either. I think that is because nobody has ever actually defined the physical energy release process that is unique to "magnetic reconnection" and no self respecting electrical engineer talks about magnetic fields making and breaking connections. More importantly no one has ever demonstrated that "magnetic reconnection" works in a lab. In this particular instance, that is unacceptable. There is absolutely no scientific reason this idea should not be put to a test. I the father of MHD theory doesn't buy the idea, then I'll need to see some evidence that it exists and has the effects it claims to have on plasma. I see nothing from controlled testing that leads me to believe that magnetic reconnection occurs in nature. That's a *big* problem IMO.
No, I've not read his books yet. Your enthusiasm is so noted. Terry's book sounds more interesting to me personally so that book will go to the top of my "to read" list. :)
Well, I'm definitely not a believer in string theory, so I have to agree with you on this point.
It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland
RE: While rather heavy,
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Thanks for that link, I'll have a crack at it.. :-)
Nice one! :-) I was recalling a late 1970's lecture by Feynman, so it's been drilled down even further since.
This deserves a quote from Lisa Randall ( Warped Passages p9 ):
I once heard a physicist use the phrase 'the electron abstraction', and when I queried that he asked if I'd ever seen one. He was predominantly an experimenter and made me focus on the whole shebang of measurement. He didn't really disbelieve in electrons. He was teaching us to be sure as we can about what we think we are detecting. While dear Schroedinger's cat gets killed ( recurrently, it would seem! ) by an alpha particle triggered event sequence that climbs up the distance scales - for which entity did you put a saucer of milk down? The high energy physics ( terrestrial colliders ) program has been terrific in resolving smaller scale detail. But like repeatedly blowing up houses to count doorknob fragments I get a feeling we are missing some important subtler issues - like whether you twist the knob to the left or right to open the bathroom door. Alas we can't do an Alice ( or an Edwin Abbott ) and vary our personal sensory granularity to suit. So we have to make do with effective ( scale dependent ) theories.
The really weird thing is that sometimes the math is well ahead of us. The neutrino was proposed long before it's discovery, due to energy budgets not agreeing. The positron likewise, as it popped out as an alternate solution to Dirac's QM treatment of the electron. Also Gelmann's 'eight-fold way' tamed the particle zoo and preceeded actual detection of the hard sub-nucleon-size mass concentrations we now call quarks. Oh, and not to forget Uranus and Neptune being emitted ( with some luck too ) by the numerical orreries of classical celestial mechanics. Penrose has a lot to say on this area. ( I am on my third attempt at plowing into 'The Road To Reality' ).
Cheers, Mike.
( edit ) NB Gell-Mann
I have made this letter longer than usual because I lack the time to make it shorter ...
... and my other CPU is a Ryzen 5950X :-) Blaise Pascal
I know this is off-topic, but
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I know this is off-topic, but I'm very curious.
Michael Mozina (MM) has made many statements, in this thread, about what he apparently regards as the inviolable criterion for any theory of physics.
Some examples:
I have already asked Michael several questions concerning the consistency between these 'no shades of grey' statements and his (apparent) explicit endorsement of hypotheses which incorporate, at their core, ideas which seem to be coloured deepest grey.
Here I would like to engage in a preliminary exploration of the (for now loosely worded) hypothesis that MM applies his oft-stated fundamental criterion in a very selective way, to wit: it is applied exclusively to 'non-baryonic dark matter', 'dark energy', and 'inflation'.
To test this hypothesis, I shall use as input all MM posts in this thread, to date, as they relate to MOND.
At the outset, I should note that the test *assumes* that MM is well aware that all internally consistent MOND proposals, published to date^, cannot be empirically tested, under controlled conditions, anywhere closer than ~10kpc from the solar system, even in principle. Of course, should independently verifiable, objective evidence emerge that MM was not, before now, aware of this central feature of such MOND proposals, the test (below) becomes moot.
There are, I think, four substantive statements, by MM, on MOND, in this thread:
In addition there is this:
While this does not, explicitly, mention MOND, there can surely be no doubt that "magic force" fits MOND perfectly - it's an ad hoc, arbitrary modification of Newtonian gravity; as a "proposed solution", we cannot "demonstrate that [it] exists in controlled empirical ways"; and so on.
Note too that MM states - unequivocally - that this is "where my primary criticism of standard theory comes from".
It would thus seem, based on the empirical evidence, presented above, that the (admittedly loosely-worded) hypothesis is:
a) not falsified
b) explicitly verified.
^ check out the lists of publications ('scientific literature') on the MOND Pages website (http://www.astro.umd.edu/~ssm/mond/).
RE: [snip] RE: Keep in
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Thanks MikeH! :-)
In other fora, I've been banging on about this for quite some time, and while I've read Randall's book (more than once actually), I missed that gem; thanks.
One aspect that attracts me to Einstein@Home (and LIGO and GW detectors in general) is the imminent possibility of having another, non-electromagnetic, window on the universe beyond our solar system. And equally fascinating is the possibility of iron-clad null results, with all that will entail for GR.
Even better: already one new window is, very slightly ajar - ultra-high energy cosmic rays ... and a third should open within the next decade - neutrino astronomy.
The 'we observe the universe only through the filter of theory' is doubly applicable to astronomy (beyond the solar system) - no Earthly lab will ever be able to do controlled experiments on an object with a mass of a few million sols and a radius of < 100,000 km (for those who may miss this, that's a not-too-inaccurate description of something astronomers call SgrA*), for example, and we only know of the existence of such objects via a doubly lengthy chain of theory-laden measurements.
IIRC, Gell-Mann himself didn't intend quarks to be 'real' but rather a very neat application of math that merely *described* the behaviour of (real) protons, neutrons, pi mesons, etc!
To your list I think you might add the experiments which tested the EPR paradox - the (math-based) predictions preceded the experiments by decades, for all the deeply discomforting implications of a 'QM 1, Einstein 0' result.
It's also very easy to overlook the hundreds and hundreds of 'downstream' particle discoveries, which flowed from the Standard Model ... Psi/J get star billing (because it was the first), but it's so easy to forget that even one 'blank cell' in the huge table would have caused a great deal of head-scratching. My personal favourite is the tau neutrino, alongside the determination of the width of the Z (or was it the W?), which thus ruled out any other, 'light', 'non-sterile' neutrinos.
RE: It seems I have not
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Well, let's look at the verbiage they did use in the press release:
That sure sounds like Alfven's description of a magnetic rope to me.
Bangs from electrical currents in the solar wind Nereid? How can you simply ignore the implications of this statement? It's an *electric* universe Nereid. Even our friends at NASA are noting this fact. Are you going to just ignore this data or what?
No, but you claimed that we were studying "magnetic reconnection" with in-situ measurements!
That statement is ridiculous Nereid. We can't "study" something from space in uncontrolled observations. We could only hope to demonstrate that Alfven was incorrect about "magnetic reconnection" in a lab, we could never do so in pure observations from space. You can't even explain what is unique about "magnetic reconnection" energy releases, and therefore it is absolutely impossible to you to study it in space or in a lab.
Is there a reason that you personally need to deny what they said in their press releases? Are you hoping these field aligned currents are something other than a 'magnetic ropes'? What else is going to form those twisted rope structures in light plasma, transfer that much energy through light plasma, and create those "bangs" they were talking about?
I'm directly questioning your personal statement about how we were "studying" magnetic reconnection. NASA press release said absolutely nothing that I could find fault with. They even talked about the electrical currents in the solar wind. NASA seems to be openly discussing the electrical currents in space, whereas you continue to deny it's role in astronomy. If you aren't careful Nereid, you'll be the last individual on the planet to notice what everyone else has already noticed. The universe is electric. Evidently the universe itself is 'against the mainstream' too. I guess you'll just have to ban the whole universe from BAUT. ;)
It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland
RE: RE: It seems I have
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http://www.pppl.gov/polImage.cfm?doc_Id=29&size_code=Doc
--PPPL Collaboration Yields Important Fusion Energy
Science Advance – on the 'sawtooth' instability plasma phenomenon and magnetic reconnection.
Professor Drake and his current focus on magnetic reconnection - “Key discoveries in magnetic reconnection made by Dr. Drake and his colleagues center around the role of whistler waves in driving and controlling magnetic reconnection. Traditionally it was believed that the Alfven wave played the key role in driving reconnection. At small scales, however, electron and ion motion decouple and the dynamics is controlled by whistler waves. �
Magentic reconnection - “Magnetic reconnection is a phenomenon which is of particular importance in solar system plasmas. In the solar corona, it results in the rapid release to the plasma of energy stored in the large-scale structure of the coronal magnetic field, an effect which is thought to give rise to solar flares. Small scale reconnection may play a role in heating the corona, and, thereby, driving the outflow of the solar wind. In the Earth's magnetosphere, magnetic reconnection in the magnetotail is thought to be the precursor for auroral sub-storms....�
Mangetic reconnection region larger than 2.5 million km found in solar wind - “Using the ESA Cluster spacecraft and the NASA Wind and ACE satellites, a team of American and European scientists have discovered the largest jets of particles created between the Earth and the Sun by magnetic reconnection... �
Direct observation of 3D magnetic reconnection - “...multipoint measurements by the Cluster mission reveals, for the first time, a direct observation of a 3D magnetic field topology at the magnetopause, resulting from magnetic reconnection at multiple sites...�
Double Star and Cluster witness pulsated reconnection for several hours - “...These results improve our knowledge on how, where and under which conditions the solar wind manages to penetrate the Earth's magnetic shield on the flank of the magnetosphere... � (emphasis added)
I dunno Michael, biggest cosmological mystery to me right now is how anyone can say the universe is electric instead of electromagnetic....
And here's another example of a solar model, and not just some observations and educated guesses. If you indeed had a working solar model, then it would be possible to show how it's equivalent to the standard one, because the standard one works, and is successful at reproducing observations over the course of a star's lifetime, as well as producing scenarios of stellar interiors that agree with both standard physics *and* subsequent measurements, so then by comparing the variables in your model to those in the standard one, it would be possible to make great strides, I would think....
Standard Solar Model
Please pay particular attention to Fig. 3, showing that “most stellar energy production occurs in the core.� (Too bad there is no other model [that I'm aware of] showing that most energy can be produced in any other region other than the core, but then there's a lot of physics to consider besides electricity....)