4096 4096 pixels on the solar photosphere by the Helioseismic and Magnetic
Imager (background image). We cross correlate wave field records of temporal length T at points on opposing quadrants (blue with blue or red with red).
From New York University: Researchers create ‘MRI’ of the sun’s interior motions
A team of scientists has created an “MRI” of the Sun’s interior plasma motions, shedding light on how it transfers heat from its deep interior to its surface. The result, which appears in the journal the Proceedings of the National Academy of Sciences, upends our understanding of how heat is transported outwards by the Sun and challenges existing explanations of the formation of sunspots and magnetic field generation.
The Sun’s heat, generated by nuclear fusion in its core, is transported to the surface by convection in the outer third. However, our understanding of this process is largely theoretical—the Sun is opaque, so convection cannot be directly observed. As a result, theories largely rest on what we know about fluid flow and then applying them to the Sun, which is primarily composed of hydrogen, helium, and plasma.
Developing a more precise grasp of convection is vital to comprehending a range of phenomena, including the formation of sunspots, which have a lower temperature than the rest of the Sun’s surface, and the Sun’s magnetic field, which is created by its interior plasma motions.
In order to develop their “MRI” of the Sun’s plasma flows, the researchers examined high-resolution images of the Sun’s surface taken by the Helioseismic and Magnetic Imager (HMI) onboard NASA’s Solar Dynamics Observatory. Using a 16-million pixel camera, HMI measures motions on the Sun’s surface caused by convection.
Once the scientists captured the precise movement waves on the Sun’s surface, they were able to calculate its unseen plasma motions. This procedure is not unlike measuring the strength and direction of an ocean’s current by monitoring the time it takes a swimmer to move across the water—currents moving against the swimmer will result in slower times while those going in the same direction will produce faster times, with stronger and weaker currents enhancing or diminishing the impact on the swimmer.
What they found significantly departed from existing theory–specifically, the speed of the Sun’s plasma motions were approximately 100 times slower than scientists had previously projected.
“Our current theoretical understanding of magnetic field generation in the Sun relies on these motions being of a certain magnitude,” explained Shravan Hanasoge, an associate research scholar in geosciences at Princeton University and a visiting scholar at NYU’s Courant Institute of Mathematical Sciences. “These convective motions are currently believed to prop up large-scale circulations in the outer third of the Sun that generate magnetic fields.”
“However, our results suggest that convective motions in the Sun are nearly 100 times smaller than these current theoretical expectations,” continued Hanasoge, also a postdoctoral fellow at the Max Plank Institute in Katlenburg-Lindau, Germany. “If these motions are indeed that slow in the Sun, then the most widely accepted theory concerning the generation of solar magnetic field is broken, leaving us with no compelling theory to explain its generation of magnetic fields and the need to overhaul our understanding of the physics of the Sun’s interior.”
The study’s other co-authors were Thomas Duvall, an astrophysicist at NASA, and Katepalli Sreenivasan, University Professor in NYU’s Department of Physics and Courant Institute. Sreenivasan is also Senior Vice Provost for Science and Technology for the Global Network University at NYU and Provost of Polytechnic Institute of NYU.
===========================================================
ANOMALOUSLY WEAK SOLAR CONVECTION
Shravan M. Hanasoge y and Thomas L. Duvall, Jr. z and Katepalli R. Sreenivasan
Convection in the solar interior is thought to comprise structures on a spectrum of scales. This conclusion emerges from phenomenological studies and numerical simulations, though neither covers the proper range of dynamical parameters of solar convection. Here, we analyze observations of the wavefield in the solar photosphere using techniques of time-distance helioseismology to image flows in the solar interior. We downsample and synthesize 900 billion wave-feld observations to produce 3 billion cross-correlations, which we average and fit, measuring 5 million wave travel times. Using these travel times, we deduce the underlying flow systems and study their statistics to bound convective velocity magnitudes in the solar interior, as a function of depth and spherical-harmonic degree l. Within the wavenumber band l < 60, Convective velocities are 20-100 times weaker than current theoretical estimates. This suggests the prevalence of a different paradigm of turbulence from that predicted by existing models, prompting the question: what mechanism transports the heat ux of a solar luminosity outwards? Advection is dominated by Coriolis forces for wavenumbers l< 60, with Rossby numbers smaller than ~10-2 at r/Rθ= 0.96, suggesting that the Sun may be a much faster rotator than previously thought, and that large-scale convection may be quasi-geostrophic. The fact that iso-rotation contours in the Sun are not co-aligned with the axis of rotation suggests the presence of a latitudinal entropy gradient.
paper here: http://arxiv.org/pdf/1206.3173.pdf
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And now, although by now i mean close to what, 5 years ago, there is direct laboratory evidence that plasma causes red-shifts, but that’s irrelevant because it opposes standard interpretation of red-shift right?
http://www.sciencedirect.com/science/article/pii/S0030402608000089
Steven says:
July 14, 2012 at 9:15 pm
And now, although by now i mean close to what, 5 years ago, there is direct laboratory evidence that plasma causes red-shifts, but that’s irrelevant because it opposes standard interpretation of red-shift right?
Many things produce a red-shift, all it takes is some movement away from the observer. In case of the plasma red-shift that the paper is about, the creation of the plasma by the laser pulse expands the plasma [it is hot] and the expansion creates the small red-shift. This is just a small Doppler effect. The cosmological red-shift is not a Doppler effect. The cosmic microwave red-shift has its wavelength red-shifted by a factor of some 1100. Which is huge. The farthest red-shifted galaxies are red-shift about 10 times.
No, that is where you are incorrect, Please, show me one single paper about red-shift that was not performed in a medium???? The Doppler effect only occurs because of a medium. Light IS Doppler shifted because it occurs in a medium, the plasma of relatively newly ejected quasars. Your entire premise of velocity = red-shift only supports this since it is a Doppler effect.
Leif Svalgaard, I am curious about your earlier references and seeming belief that magnetic fields can be or have been created without a moving charge(current). The Biermann battery paper you refer to mentions and uses assumed conditions in the early universe whilst deriving its result. You refer to magnetic fields already there at the begining of time, and to the situation that there was no plasma for several million years after the BB. For the sake of total disbelievers in the BB, like myself, who take all talk of conditions at this time as being totally speculative and unlikely, how would you explain the origins of the magnetic fields found pretty much everywhere we look, if not by electric currents in some form, in particular the origins of the fields so apparent in those wonderful SDO images of the solar surface?
Steven says:
July 15, 2012 at 7:37 am
No, that is where you are incorrect, Please, show me one single paper about red-shift that was not performed in a medium???? The Doppler effect only occurs because of a medium.
The cosmological red-shift is not a Doppler shift and has nothing to do with any medium. And, in any case, a Doppler shift does not require a medium as light propagation does not require a medium. Here is an accessible explanation of the difference http://curious.astro.cornell.edu/question.php?number=278/
Coolest paper and thread. So if there may be no deeper dynamic process, what would the deeper layers be doing instead?
Or rather, what other effects would a slower deep dynamic process have that could be seen on the surface, if anything? And does it change speeds?
Peter Willey says:
July 15, 2012 at 7:57 am
For the sake of total disbelievers in the BB, like myself, who take all talk of conditions at this time as being totally speculative and unlikely, how would you explain the origins of the magnetic fields found pretty much everywhere we look, if not by electric currents in some form, in particular the origins of the fields so apparent in those wonderful SDO images of the solar surface?
An important word here is ‘disbeliever’. Scientists are not ‘believers’, but go by the observed evidence [there is a small elements of belied though: that the laws of physics back then were the same as today. We see no evidence to the contrary, and the use of ‘believe’ is restricted to mean ‘think’, so ‘I believe so’ just means ‘I think so’].
Magnetic fields on macroscopic scale are caused by currents, but currents are generated and maintained using magnetic fields. That raises the problem where the very first magnetic fields came from. A plausible answer is the Biermann Battery Effect.
People often say ‘yes but in the laboratory we observe currents in plasma’, but that current is externally produced. Turn of the power to the laboratory and try to see how much current comes out of the plasma [if you find a lot, then let me in on the deal as I would no longer buy electricity from PG&E, but simply hook up to your laboratory]. So, where does the external power come from? Perhaps from steam or water turning a large conductor [cobber windings] in a strong magnetic field, like here: http://en.wikipedia.org/wiki/Electricity_generation :
” electricity is generated by the movement of a loop of wire, or disc of copper between the poles of a magnet”
The wonderful SDO images show what magnetism can do.
“If the Sun did not have a magnetic field, it would be as uninteresting a star as most astronomers believe it to be.” from http://www.leif.org/EOS/solarinterior.pdf
Pamela Gray says:
July 15, 2012 at 9:19 am
Or rather, what other effects would a slower deep dynamic process have that could be seen on the surface, if anything? And does it change speeds?
Be careful with that word ‘dynamic’. The convection that moves heat from the deep to the surface is ‘dynamic’. The creation of magnetic fields is done by the ‘dynamo’. Although the first five letters are the same, the physics is very different. What the observations probably mean is that the dynamo is not deep, but shallow. The data supporting this are, of course, taken at the surface, so there is ‘some’ effect, but very hard to see. Requires, the paper says, “900 billion wave-field observations”.
Since I see alot of discussion about it, here is an interesting article of the subject of Relativity and the Doppler effect. It should induce some interesting thought’s for those interested. Modern science is by no means the absolute truth, and there is a distinct possibility that premise behind General and Special Relativity is incorrect. It wouldn’t be the first time in humanities history that we have made a faulty inference.
http://www.gestaltreality.com/energy-synthesis/eric-dollard/the-theory-of-anti-relativity-by-e-p-dollard/
Leif Svalgaard, thank you for your reply, to which my response is :-Currents are generated and maintained by magnetic fields, which are themselves generated and maintained by those same currents,surely. Classic chicken and egg situation, which came first? The coin in my hand has two faces, one didn`t cause or precede the other,they are two aspects of the same thing. If the laws of physics change over time we have many problems in understanding anything, so in the absence of contrary evidence we assume that they remain constant. So if magnetic fields on a macroscopic scale are caused by currents today then they have always been so caused. It is when we talk about a begining of time that we cause ourselves all sorts of unneccesary problems. I do not “believe” in a BB because there is no compelling observational evidence for such an occurence. The Gemini deep deep survey for example, using text book scientific methods for increasing the signal relative to background noise, obtained spectral features from the so called redshift dessert, a red shift of approx 2,that greatly resemble the spectra of galaxies such as our own today. At that redshift, on current understanding, the universe was around 10 billion years old, so that observation alone casts great doubt on any BB theory that claims the universe is 14 billion years old. The “shadows” of more recent galaxies have not been seen in the CMB as they should have been if the radiation is what it is claimed to be.Two examples of why I don`t “believe” in BB. So back to the original question, is there any observation that today indicates magnetic fields are caused by other than electric currents? There may well be, but if so I`m not aware of them.
Peter Willey says:
July 15, 2012 at 3:07 pm
So back to the original question, is there any observation that today indicates magnetic fields are caused by other than electric currents? There may well be, but if so I`m not aware of them.
The issue is what causes the electric currents? The answer is moving a conductor in a magnetic field, giving rise the the Chicken and Egg question. The answer to that is the Biermann Battery Effect.
Peter Willey says:
July 15, 2012 at 3:07 pm
The Gemini deep deep survey for example, using text book scientific methods for increasing the signal relative to background noise, obtained spectral features from the so called redshift dessert, a red shift of approx 2,that greatly resemble the spectra of galaxies such as our own today
As you can see from the latest Gemini conclusions: http://www.gemini.edu/images/pio/newsletters/pdf/GF0612/GDDS.pdf
There are no discrepancies with BB. The issue is with understanding the formation of galaxies, not with BB. Tell me where in that overview [exact words, please] doubt is cast upon BB.
The “shadows” of more recent galaxies have not been seen in the CMB as they should have been if the radiation is what it is claimed to be.
Links please. The resolution of the CMB isn’t fine enough to show any “shadows” anyway.
These two ‘examples’ are very flimsy grounds to throw away all the strong evidence of BB. At best they have to do with interpretation of difficult to obtain data.
Our theory is good enough to be taught at NASA now. Even they can no longer deny the facts so bring in the experts.
Steven says:
July 16, 2012 at 11:51 am
Our theory is good enough to be taught at NASA now.
“taught” ?? NASA [as any other scientific institution] occasional invites people [sometimes even cranks – I myself has given presentations there] to give a presentation of their ideas. This does not mean that they ‘bring in the experts’.
But you are still evading the issue:
Why would you ever think I would get a different answer?
As far as I am concerned you have no answer at all. You did not show the derivation of the formulae, did not show the formulae, did not show the calculation.
So provide these things. I think that you have not so, simply because you cannot. Prove me wrong.
Steven says:
July 16, 2012 at 11:51 am
Our theory is good enough to be taught at NASA now.
an example of Scott’s ignorance: in his presentation he says that Langmuir hijacked the term plasma from biology because it shares a characteristic with space plasma “they are both cellular”. But the blood plasma is also not cellular, it is what is between the blood cells http://en.wikipedia.org/wiki/Blood_plasma “Blood plasma is the straw-colored/pale-yellow liquid component of blood that normally holds the blood cells in whole blood in suspension”
I told you 3 times already Leif, I use the exact same formula as you because those formulas are derived from Maxwell’s equations, as is almost all of relativity.
And dont try to misdirect the plasma and blood issue, good try though. It was termed as similar to blood plasma because like blood, at the knowledge available at that time foreign invaders would be sheathed and separated, like white blood cells surround and isolate foreign invaders, Differing electrical charges in plasma are separated from one another by double layers. Since the atom consists of gluons as force carriers I could just as easily say they or other smaller particles are these particles that hold the cells in suspension.
Do you believe in action at a distance?
i assume not as its not considered valid in standard cosmology, so since the electron neither recedes from, nor crashes into the nucleus, then smaller particles transferring charge, carrying it along between nucleus and electron exist. These act in the same manner, so your comments are nothing more than an attempt to distract from the issue, or else you would of deffinately realized the error of your comment.
REPLY: OK that’s it for me, mixing blood plasma and electrical plasma arguments are so far off the deep end it doesn’t deserve any further waste of bytes and my time. Thread closed, now take your [unprintable] commentary elsewhere. All further posts from you go immediately to the bit bucket, so don’t try to thread bomb other threads like you did yesterday – Anthony