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~~[MERIT]~~ · 08-15-2012, 09:07 PM

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AN ELECTRIC SUN

Since we've come this far in questioning today's generally accepted cosmology, we might as well go the whole hog and look at some of the reasons for thinking that the Sun--and all the other stars--might not, in fact, be what we've always been told they are at all.

The standard model of the Sun traces back to the work of Sir Arthur Eddington in the 1920s, which was based on maintaining an equilibrium between the compression of a gaseous sphere under gravity, and an expansive force due to an interior heat source. What kind of source could maintain a prodigious enough output of energy to sustain the mass of the Sun at the size observed remained an unanswered question. In the following decade, studies of nuclear physics established the mechanism whereby hydrogen nuclei (protons), given sufficient energy, can fuse together to form helium atoms in a process that yields significantly more energy per reaction than even that obtained from uranium fission. The Sun was known to consist predominantly of hydrogen, and so the story recounted in all the textbooks today took shape, of the Sun being powered by thermonuclear reactions deep in the core, ignited by heat generated through gravitational compression. All observational data is then interpreted in terms of this assumption.

Although accepted practically universally as beyond question, the model does have problems. For a start, the density calculated for the center of the present-day Sun is about a hundred times too low to ignite a thermonuclear process. Hence, the creation of a star from a collapsing cloud of the Sun's present mass would seem to be ruled out. At the calculated temperature of thirteen million degrees K, the protons would possess insufficient thermal energy to overcome the mutual repulsion of their positive charges, as would be necessary for them to get close enough to fuse.

The response is to invoke quantum mechanical tunneling, which is the curious ability of quantum objects like protons to occasionally "tunnel" through energy barriers that they don't possess enough energy to climb over. It would be as if a marble rolling around in a soup dish without the momentum to make it to the rim were suddenly to appear outside. Such tunneling permits fusion only when the protons approach head-on, which occurs in a minuscule proportion of collisions. The entire process postulated to occur does so under conditions that are far beyond laboratory experience, and involves approximations unjustified by anything but a need for mathematical simplification. Undaunted, the majority of theorists, seeing no alternative to fusion, conclude that since the thermonuclear Sun obviously did ignite, the requisite temperature must exist.

According to the model, the hydrogen gas gravitates into layers of ever increasing density and temperature inward from the Sun's surface to its center. The 1970s brought the first reports of the entire solar surface being observed to expand and contract rhythmically through an amplitude of about 10 km, with a period of 2 hours, 40 minutes. On the basis of the simplest interpretation that this represented a purely radial pulsation, this periodicity is almost precisely what would be expected if the Sun were a homogeneous sphere having equal density ("isodense") throughout--like the air in a balloon. The conventional model predicts a natural period of about an hour, corresponding to a steep density rise in the interior. The difference may sound trivial to some, but the short answer is that an such an isodense Sun is incompatible with a thermonuclear engine at the center--the core would be too cool. Suggestions followed that perhaps the pulsations were not pure radial motions but higher harmonics of some more fundamental gravity wave, but they were not enthusiastically received. That this was pure fudging to preserve the theory was obvious, and it seemed strange that a high harmonic should be dominant. The other response from the mainstream school was to ignore it.

The net energy-producing reaction in the standard model is known as the proton-proton, or P-P reaction. It converts four protons plus two electrons into a helium nucleus (consisting of two protons and two neutrons), two neutrinos, and six photons. Since the Sun's photosphere--the white-hot sphere of light that we see--and the underlying layers enveloping the core are opaque, the photons would have to percolate to the surface through countless absorptions and re-emissions by matter in a process estimated to take 100,000 years or more. Sixty percent of the energy from the P-P reaction is carried away by the neutrinos, theorized as tiny massless particles which in contrast to the photons do not interact appreciably with matter and escape from the Sun at the speed of light. The thermonuclear model has the Sun producing around 1.8 x 1038 neutrinos per second, of which, at the distance of the Earth, 400 trillion would pass through a human body (giving some idea of how big a number 1038 is).

Neutrinos react so weakly with matter that this has no affect on us at all. However, suitably designed devices can register neutrinos produced artificially in nuclear reactors, and in 1965 a system located two miles underground in a South African mine (to screen out other particles from extraneous sources) detected neutrinos created by cosmic ray reactions in the upper atmosphere. This offered a unique means of verifying the otherwise invisible thermonuclear processes believed to be taking place deep in the Sun, and thus of testing the model.

The basic P-P reaction produces relatively low-energy neutrinos not amenable to detection by earlier instrumentation. However, the model implied that a further but rarer side reaction forming a beryllium nucleus should occur, that also produces a higher-energy neutrino. Accordingly, a detector designed specifically to look for high-energy solar neutrinos was constructed in the Homestake Gold Mine at Lead, South Dakota, and went into operation in 1967. It was followed in the 1980s by similar but more sensitive experiments at Kamiokade in Japan. By the 1990s, devices were being built to detect lower-energy P-P neutrinos also.

The results were devastating for the standard theory. Low-energy counts were so low that the experimental uncertainties made reliable interpretation impossible, while the counts at high energy remained obstinately at around a third of what was expected. Attempts were made to invoke a hypothetical particle dubbed the WIMP (Weakly Interacting Massive Particle) to cool the solar core, causing it to produce fewer neutrinos, but since its existence had never been actually demonstrated, and the sole motivation for wheeling it in was to save the theory, few found the approach satisfying.

The zoo of elementary particles admits three "flavors" of neutrino, known as "electron" (ε), "muon" (μ), and "tau" (τ) types. If the neutrino were allowed to possess a tiny amount of mass after all, the probabilistic nature of the physics said it would be possible for them to interconvert, one to another. At lower energies the ε type has a means of interacting with mass that depends on electron density and which isn't available to the μ and τ types. Diligent study of the equations yielded the intriguing possibility that in their passage through the dense interior of the Sun, some of the ε types could be changing into μ types, which would explain why detectors looking for ε types weren't finding as many as they should.

Homestake could detect only ε, while Kamiokade could detect ε and some μ. Cosmic rays bombarding the upper atmosphere produce μ neutrinos, which would add to the flux of μ types arriving after conversion from the Sun. The conversion rate was expected to fluctuate from day to night, since the intervention of the Earth's mass between a detector on the night side and the solar source would add to the conversion rate. But no such effect was found. The solution proposed was that μ neutrinos traversing the Earth's core converted in τ types, which the detectors couldn't see. But the overall deficiency of low-energy ε types still persisted. To answer this, a new proposal was advanced that ε neutrinos are able to change states in a vacuum to become τ neutrinos.

Thus, while ε type neutrinos require electron interaction in the dense interior of the Sun to turn into μ types, they can become τ types in empty space--and hence undetectable; but μ types achieve the same result inside the Earth's core. And so was theory squared with observation. But a huge amount of effort had been expended over 30 years, many flags of reputation and prestige had been nailed to the resulting mast, and few were comfortable.

Then, in 2001, preliminary results from the newly built Sudbury Neutrino Observatory (SNO) in Ontario, the first to be capable of detecting all three neutrino types, brought jubilant proclamations that all was well after all. According to Physics World in July, the "Solar neutrino puzzle is solved," and "confirms that our understanding of the Sun is correct." The piece continued "The results confirm that electron neutrinos produced by nuclear reactions inside the Sun 'oscillate' or change flavour on their journey to Earth." Another article asserted, "The SNO detector has the capability to determine whether solar neutrinos are changing their type en-route to Earth . . ." 5

The first thing that should be noted here is that no results based solely on Earth-based measurements can determine whether or not anything changed en-route. If a train from New York arrives in Chicago made up of, say, 20 box cars, 10 flat cars, and 5 tank cars, no amount of sophistication or statistical juggling can establish whether changes were made at stops in between if the numbers that left New York are not known. But the claim captures the general tenor of the announcements widespread at the time and generally accepted since. However, in view of the enormous investment of material and psychic interests over 30 years, and the degree of desperation already evidenced in a determination to preserve the theory by any means, it seems that some caution might be in order here, along with a deeper look at exactly what is being claimed.

The assertion of being able to determine that flavors changed en route was based on an assumption that the μ neutrino deficit registered at Kamiokade indicated a vanishing of μ types that had been present to start with, and that they could only be accounted for by the τ types detected by SNO. There seems to be a strong element of knowing what the answer has to be, at work here. Suppose that, based on figures for New York's throughput of commerce, I've formed a model of the kind of train that I think should be put together to handle it; but I've never been able to see what actually leaves New York. Also, I have a theory that flat cars can turn into tank cars. Nobody would disagree that a mixed train arriving in Chicago with fewer flat cars than I expected is consistent with my ideas. But it can't be taken as proving them. The presence of tank cars in the train is no guarantee that any of them transformed from flat cars.

Three different reactions were used in the SNO experiment: Charged Current reaction (CC), sensitive only to ε neutrinos; Neutral Current (NC), sensitive to all (ε, μ, τ); and Elastic Scattering (ES), sensitive to all, but with reduced sensitivity to μ and τ. If total neutrino flux was the prime issue of interest, the NC experiment would be the most important one. However, at the time of the announcement that measurement was stated as being not available, to be reported at a later date. As far as I'm aware, that's still the situation. Despite the heavy public relations treatment, my inclination is that the jury is still out on this one. And even if final numbers should be presented that are consistent with the standard theory, once again a conclusion can't be taken as proof of the premise. (If it rains, the lawn will be wet. But a wet lawn isn't proof that it rained.) Other causes can produce similar end results, as we shall see. And the other difficulties with the standard thermonuclear model still remain.

Another problem concerns the Sun's photosphere--the first layer outward from the interior that we see, that gives off practically all the radiant energy that we think of as sunshine. If the Sun were indeed in a condition of mechanical equilibrium maintained to sustain the dissipation of internally generated thermal energy, then it might well be expected to "end" right there. The mechanism gives no obvious cause for anything more to happen beyond the photosphere, and unimpeded radiation into space would probably afford the best means for getting rid of the photons finally emerging at the surface. Yet the photosphere forms merely the base of an atmosphere extending for enormous distances and exhibiting astonishing complexity.

Perhaps the most striking feature of the photosphere is its lumpy "rice grain" structure. Instead of being uniformly bright as might be expected, the surface appears as made up of millions of high-luminosity granules of hot plasma in a background of lesser luminosity forming a network between them--the effect being like looking down on closely packed fluffy clouds. The granules average about 1000 kilometers in diameter and come and go, splitting and merging, with lifetimes in the order of minutes. Budding granules sometimes appear to rise from below, pushing aside or replacing older ones; otherwise they show little lateral movement.

The accepted explanation is that the granules are the tops of convection current cells, which provide the mechanism for conveying heat from its origins deep in the Sun, through the opaque interior to the surface, where it is radiated away. The cooled material then descends back between the rising columns, losing brilliance and appearing darker in comparison. Although seemingly consistent and straightforward, this view has the problem that at the temperatures and densities involved, the motion expected would be violently turbulent and chaotic. This is in stark contrast to the orderly pattern actually observed, with its structure and symmetry, where each granule seems to fulfill a localized function constrained by forces that create barriers to lateral motion and diffusion. Another peculiarity is the photosphere's differential rotation, which varies from 25 days at the solar equator to 35 days near the poles. Strong convection currents of the kind proposed should bring about a uniformity of rotation.

It is true that classical studies of convection in fluids can reproduce the structure of rising cells separated by descending flows said to be responsible for solar granularity. But assuming the validity of terrestrial laboratory physics under the conditions at the solar surface seems questionable, especially when no account is taken of the plasma's electrical nature. If such an assumption is granted, applying it then fails by its own criteria. A quantity known as the Reynolds Number, combining several physical parameters, exhibits a critical value beyond which ordered motion gives way to highly complex turbulence that precludes orderly flows. Analysis of data from the photosphere points to a Reynolds Number greater than critical by a factor of 100 billion. This discrepancy is not trivial. Similarly, the critical value of a quantity designated the Rayleigh Number, specifically devised as a criterion for the formation of convection cells, is exceeded by a factor of 100,000. And even if structured convection does exist in the Sun's depths, chaotic motion should still characterize the uppermost layer of the photosphere that we see, where gas density diminishes rapidly with height and both the Reynolds and Raleigh Numbers soar. It seems that the granulations can be explained by convection only by disregarding everything that is known about convection.

Conventional theory would predict an atmosphere above the photosphere only a few kilometers thick. Actually found, however, is the chromosphere, an extraordinarily active region whose reddish glow is visible during solar eclipses. The inner chromosphere is ravaged by enormous, short-lived jets of material called somewhat belittlingly "spicules," measuring hundreds of kilometers in diameter and towering thousands high. Above those are found the even greater twisting arcs of "prominences," and locally disruptive explosive solar "flares" that can extend over 20,000 kilometers.

The temperature of the chromosphere rises sharply with altitude. Beyond it lies the corona, an envelope of hot, rarified gas reaching to an indefinite distance among the planets. The lower parts show a faint emission spectrum (excited atoms releasing excess energy), consistent with light scattered by electrons moving in a temperature of one to two million degrees K. Higher parts of the corona show the absorption spectra of background sunlight scattered by intervening atomic particles, along with emission lines indicating the presence of very hot, tenuous gas. The corona behaves like an expanding gas, too hot to be bound by gravity to the Sun. It provides the source of the "solar wind" of particles, primarily protons, flowing outward through the Solar System into interstellar space. A curiosity is that the solar wind accelerates as it moves away from the sun, whereas evaporated protons ought, by normal considerations, to be retarded by the Sun's gravity.

From the postulated heat source in the Sun's center, the temperature falls steeply toward the photosphere, forming the gradient along which energy flows outward. At the same time, the temperature in the atmosphere falls steeply in the opposite direction, the two gradients producing a trough of 6,000-4,000o K (granule or intervening space) at the photosphere. By basic physics, thermal energy should be trapped at this minimum until the trough is eliminated. Here we have another curiosity, this time fundamental. But it doesn't appear to have perturbed anyone overly. Since it's known that the energy source has to be inside the Sun, the gradients must sustain themselves somehow.

Earlier, when talking about Arthur Eddington's model of a self-gravitating ball of gas, we said that an internal source for the Sun's heat had to be presumed, since the astronomy of the times (and still, largely, that seen today) was essentially a science of isolated bodies interacting only through gravity. But we've already suggested an alternative picture of the whole universe as an interconnected power grid in which enormous energies represented by charge separation on a cosmic scale are conveyed by electric currents flowing between and through galaxies, down to the level of driving the processes that create their constituent star systems. Electric fields are potentially (another unintended pun) the biggest store of energy in the universe. That being so, a further question that presents itself is: Might the same source not power those stars too? In short, let's admit the ultimate heresy and consider that perhaps stars aren't driven by thermonuclear engines deep in their interiors at all.