packz ha scritto:
se non altro rimani in topic
Pquantum ha scritto:
Volevo anche chiedervi se tra di voi c'è qualcuno interessato a visitare il CERN di ginevra, mi piacerebbe tanto visitare l'acceleratore.
Bye
bisogna ricordare che oltre il 40% dell'energia prodotta dalle stelle è dovuta all'effetto tunnel di Gamow,e non bisogna dimenticare che è la miglior teoria che si riscontra con l'esperimento,in quanto le previsioni teoriche si accordano incredibimente con l'esperimento.
ivan ha scritto:
Citazione:
bisogna ricordare che oltre il 40% dell'energia prodotta dalle stelle è dovuta all'effetto tunnel di Gamow,e non bisogna dimenticare che è la miglior teoria che si riscontra con l'esperimento,in quanto le previsioni teoriche si accordano incredibimente con l'esperimento.
Bad news:
Rigel: 11000 K
Sirio: 9900 K
Sun: 5780 K
etc, etc.
Dei dati un pò freddini per oggetti che dovrebbero girare a fusione termonucleare.
Quindi : che le stelle siano bombe termonulceari per adesso son solo congetture guarrafondaie.
ivan ha scritto:
Vorrei ricordare che nessuno sa ne potrà mai sapere cosa c'è all'interno di una stella.
Nessuno può mettere lì un termometro o una termocoppia e dire si è vero, la temperatura è XXXX +/- UU K.
L'unica cosa che possiamo misurare con una certa attendibilità è la temperatura media superficiale di una stella.
E i dati che abbiamo mal si prestano a essere interpretati come il risultato di una fusione termonucleare.
ivan ha scritto:
Dimenticavo: e non vi è nessuna evidenza sperimentale che i protoni in un qualche modo decadano, al massimo vi è evidenza sperimentale più che certa che decadono i neutroni.
Projecting Nuclear Fusion onto the Sun
What is the source of the Sun’s light and heat? Throughout history people have proposed answers to this question that have always reflected human experience. The Sun was a shining god or a “spark” cast off in the creation. Later it was a pile of burning sticks or coal.
By the nineteenth century, astronomers had become accustomed to thinking that gravity was the dominant force in the heavens. So they began to conjecture that the energy of the Sun might be due to “gravitational collapse”, a compression of solar gases by gravity. This simple hypothesis, its proponents claimed, could provide the required energy output for a few tens of millions of years.
By the late 19th century, however, geologists were confident that Earth was much older than the astronomers’ model would allow, and the conflict between astronomy and geology continued for several decades. Then, in 1920, the British astronomer Sir Arthur Eddington combined the principle of gravitational collapse with an exciting new principle in the physical sciences—nuclear fusion. He proposed that at the core of the Sun, pressures and temperatures induced a nuclear reaction fusing hydrogen into helium.
In 1939 two astrophysicists, Subrahmanyan Chandrasekhar and Hans Bethe, working independently, began to quantify the gravitational collapse and nuclear fusion hypothesis. Bethe described the results of his calculations in a brief paper entitled "Energy Production in Stars”, published in 1939.
The model that followed the work of Eddington, Chandrasekhar, and Bethe described a “nuclear furnace” responsible for igniting stars. And for decades now cosmologists, astronomers, and astrophysicists have accepted the basic concept as fact.
In the early formulations of the “standard model” of star formation, it was said that the gravitational force within a primordial cloud leads to its progressive compression into a “circumstellar disk”, as the outer material in the cloud “falls” inward, and gravity gives birth to a star-sized sphere, whose core temperature continues to rise under increasing pressures. Collisions of atoms within the core eventually become so energetic that electrons are stripped from their nuclei, leaving free electrons and hydrogen protons (a plasma as we now understand it). In stars roughly comparable to our Sun, with envisioned core temperatures less than 15 million Kelvin, the nuclear reaction begins when hydrogen protons are joined or stuck together in the “proton-proton fusion” of hydrogen into helium.
Critics, however, pointed out that the temperatures given by standard gas laws are not sufficient to provoke nuclear fusion. They cited the “Coulomb barrier”, in this case the electric repulsion between two protons, or like charges. Once protons are fused, they could be held together by the strong nuclear force, but that force dominates only at short distances. To achieve fusion, it would be necessary for protons to cross the barrier of the repulsive electric force, which is sufficient to keep the protons apart forever. But Eddington’s successors accomplished the impossible by something called quantum tunneling, enabling an extremely small percentage of protons to simply “appear” inside the barrier at any particular time.
It is ironic that the early objections to the fusion model of the Sun focused on the powerful electric force. This was long before arrival of the space age with its discovery that the charged particles of plasma permeate interplanetary and interstellar space, and long before any systematic investigations of plasma and electricity in space.
Advocates of the “nuclear furnace” made a series of fundamental assumptions common to astronomy long before the emergence of a nuclear model of the Sun. The credibility of these assumptions was not an issue to them. They assumed that diffuse clouds of gas in space would collapse gravitationally into star-sized bodies. They assumed that the Sun’s mass could be calculated simply from the orbital motions of the planets. They assumed that Newtonian calculations of mass, coupled with standard gas laws, enabled them to determine the pressure and temperature of the Sun’s core.
The pioneers of the nuclear furnace also followed another assumption common to astronomy in their time—that the Sun and planets are electrically neutral. They gave no consideration to the role of electricity and no consideration to the role of the magnetic fields that electric currents generate.
Are the assumptions made in the first half of the twentieth century still warranted after decades of space exploration? Those proposing an electrical perspective, based on more recent data, insist that the earlier conjectures are not only unwarranted, but discredited by direct observation and measurement. They emphasize that every feature of the Sun as we now observe it, defies both the gravitational assumptions and the standard gas laws relating to pressure, density, temperature and relative motions of gases. The deepest observable surface of the Sun yields a temperature of about 6,000 degrees Kelvin. As we peer into the darker interior of sunspots we see cooler regions, not hotter. But moving outward to the bottom of the corona, the temperature jumps spectacularly to almost 2 million degrees. Thus, the superheated shell of the Sun’s corona reverses the expected temperature gradient predicted by models of internal heating.
It seems that the Sun does not even “respect” gravity. The mass of charged particles expelled by the Sun as the solar wind continues to accelerate beyond Mercury, Venus, and Earth. Solar prominences and coronal mass ejections do not obey gravity either. Nor does sunspot migration. Nor does the movement of the atmosphere, since the upper layers rotate faster than the lower, reversing the situation predicted by theory, while the equatorial atmosphere completes its rotation more rapidly than the atmosphere at higher latitudes, another reversal of predicted motions.If the Sun’s atmosphere were subject only to gravity and the hot surface, it should be only a few thousand kilometers thick instead of the hundred thousand kilometers or more that we measure. Even the shape of the Sun defies the expectations of theory. The revolving Sun should be an oblate sphere. But it is a virtually perfect sphere, as if gravity and inertia have been overruled by something else.
....
.....
For centuries, the nature of the Sun’s radiance remained a mystery to astronomers. The Sun is the only object in the solar system that produces its own visible light. All others reflect the light of the Sun. What unique trait of the Sun enables it to shine upon the other objects in the solar system?
Today, astronomers assure us that the most fundamental question is answered. The Sun is a thermonuclear furnace. The ball of gas is so large that astronomers envision pressures and densities within its core sufficient to generate temperatures of about 16 million K—producing a continuous “controlled” nuclear reaction.
Most astronomers and astrophysicists investigating the Sun are so convinced of the fusion model that only the rarest among them will countenance challenges to the underlying idea. Standard textbooks and institutional research, complemented by a chorus of scientific and popular media, “ratify” the fusion model of the Sun year after year by ignoring evidence to the contrary.
A growing group of independent researchers, however, insists that the popular idea is incorrect. These researchers say that the Sun is electric. It is a glow discharge fed by galactic currents. And they emphasize that the fusion model anticipated none of the milestone discoveries about the Sun, while the electric model predicts and explains the very observations that posed the greatest quandaries for solar investigation.
More than 60 years ago, Dr. Charles E. R. Bruce, of the Electrical Research Association in England, offered a new perspective on the Sun. An electrical researcher, astronomer, and expert on the effects of lightning, Bruce proposed in 1944 that the Sun’s "photosphere has the appearance, the temperature and the spectrum of an electric arc; it has arc characteristics because it is an electric arc, or a large number of arcs in parallel." This discharge characteristic, he claimed, "accounts for the observed granulation of the solar surface." Bruce’s model, however, was based on a conventional understanding of atmospheric lightning, allowing him to envision the “electric” Sun without reference to external electric fields.
Years later, a brilliant engineer, Ralph Juergens, inspired by Bruce’s work, added a revolutionary possibility. In a series of articles beginning in 1972, Juergens suggested that the Sun is not an electrically isolated body in space, but the most positively charged object in the solar system, the center of a radial electric field. This field, he said, lies within a larger galactic field. With this hypothesis, Juergens became the first to make the theoretical leap to an external power source of the Sun.
Juergens proposed that the Sun is the focus of a "coronal glow discharge" fed by galactic currents. To avoid misunderstanding of this concept, it is essential that we distinguish the complex, electrodynamic glow discharge model of the Sun from a simple electrostatic model that can be easily dismissed. Throughout most of the volume of a glow discharge the plasma is nearly neutral, with almost equal numbers of protons and electrons. In this view, the charge differential at the Earth’s distance from the Sun is smaller than our present ability to measure—perhaps one or two electrons per cubic meter. But the charge density is far higher closer to the Sun, and at the solar corona and surface the electric field is of sufficient strength to generate all of the energetic phenomena we observe.
Today, the electrical theorists Wallace Thornhill and Donald Scott urge a critical comparison of the fusion model and the electrical model. Given what we now know about the Sun, which model meets the tests of unity, coherence, simplicity, and predictability? Why did so many discoveries surprise investigators and even contradict the expectations of the fusion model? Is there any fundamental feature of the Sun that contradicts the glow discharge hypothesis?
Our closer looks at the Sun have revealed the pervasive influence of magnetic fields, which are the effect of electric currents. Sunspots, prominences, coronal mass ejections, and a host of other features require ever more complicated guesswork on behalf of the fusion model. But this is the way an anode in a coronal glow discharge behaves!
In the electrical model, the Sun is the “anode” or positively charged body in the electrical exchange, while the "cathode" or negatively charged contributor is not a discrete object, but the invisible “virtual cathode” at the limit of the Sun’s coronal discharge. (Coronal discharges can sometimes be seen as a glow surrounding high-voltage transmission wires, where the wire discharges into the surrounding air). This virtual cathode lies far beyond the planets. In the lexicon of astronomy, this is the “heliopause.” In electrical terms, it is the cellular sheath or “double layer” separating the plasma cell that surrounds the Sun ("heliosphere”) from the enveloping galactic plasma.
In an electric universe, such cellular forms are expected between regions of dissimilar plasma properties. According to the glow discharge model of the Sun, almost the entire voltage difference between the Sun and its galactic environment occurs across the thin boundary sheath of the heliopause. Inside the heliopause there is a weak but constant radial electrical field centered on the Sun. A weak electric field, immeasurable locally with today's instruments but cumulative across the vast volume of space within the heliosphere, is sufficient to power the solar discharge.
The visible component of a coronal glow discharge occurs above the anode, often in layers. The Sun’s red chromosphere is part of this discharge. (Unconsciously, it seems, the correct electrical engineering term was applied to the Sun’s corona.) Correspondingly, the highest particle energies are not at the photosphere but above it. The electrical theorists see the Sun as a perfect example of this characteristic of glow discharges—a radical contrast to the expected dissipation of energy from the core outward in the fusion model of the Sun.
At about 500 kilometers (310 miles) above the photosphere or visible surface, we find the coldest measurable temperature, about 4400 degrees K. Moving upward, the temperature then rises steadily to about 20,000 degrees K at the top of the chromosphere, some 2200 kilometers (1200 miles) above the Sun's surface. Here it abruptly jumps hundreds of thousands of degrees, then continues slowly rising, eventually reaching 2 million degrees in the corona. Even at a distance of one or two solar diameters, ionized oxygen atoms reach 200 million degrees!
In other words the “reverse temperature gradient,” while meeting the tests of the glow discharge model, contradicts every original expectation of the fusion model.
But this is only the first of many enigmas and contradictions facing the fusion hypothesis. As astronomer Fred Hoyle pointed out years ago, with the strong gravity and the mere 5,800-degree temperature at the surface, the Sun’s atmosphere should be only a few thousand kilometers thick, according to the “gas laws” astrophysicists typically apply to such bodies. Instead, the atmosphere balloons out to 100,000 kilometers, where it heats up to a million degrees or more. From there, particles accelerate out among the planets in defiance of gravity. Thus the planets, Earth included, could be said to orbit inside the Sun's diffuse atmosphere.
The discovery that blasts of particles escape the Sun at an estimated 400- to 700-kilometers per second came as an uncomfortable surprise for advocates of the nuclear powered model. Certainly, the “pressure” of sunlight cannot explain the acceleration of the solar “wind”. In an electrically neutral, gravity-driven universe, particles were not hot enough to escape such massive bodies, which (in the theory) are attractors only. And yet, the particles of the solar wind continue to accelerate past Venus, Earth, and Mars. Since these particles are not miniature “rocket ships,” this acceleration is the last thing one should expect!
According to the electric theorists, a weak electric field, focused on the Sun, better explains the acceleration of the charged particles of the solar wind. Electric fields accelerate charged particles. And just as magnetic fields are undeniable witnesses to the presence of electric currents, particle acceleration is a good measure of the strength of an electric field.
A common mistake made by critics of the electric model is to assume that the radial electric field of the Sun should be not only measurable but also strong enough to accelerate electrons toward the Sun at “relativistic” speeds (up to 300,000 kilometers per second). By this argument, we should find electrons not only zipping past our instruments but also creating dramatic displays in Earth’s night sky.
But as noted above, in the plasma glow-discharge model the interplanetary electric field will be extremely weak. No instrument placed in space could measure the radial voltage differential across a few tens of meters, any more than it could measure the solar wind acceleration over a few tens of meters. But we can observe the solar wind acceleration over tens of millions of kilometers, confirming that the electric field of the Sun, though imperceptible in terms of volts per meter, is sufficient to sustain a powerful drift current across interplanetary space. Given the massive volume of this space, the implied current is quite sufficient to power the Sun.
According to the caption from Astronomy Picture of the Day, (APOD), ( qui ) "In the center of a swirling whirlpool of hot gas is likely a beast that has never been seen directly: a black hole. Studies of the bright light emitted by the swirling gas frequently indicate not only that a black hole is present, but also likely attributes. The gas surrounding GRO J1655-40, for example, has been found to display an unusual flickering at a rate of 450 times a second. Given a previous mass estimate for the central object of seven times the mass of our Sun, the rate of the fast flickering can be explained by a black hole that is rotating very rapidly. What physical mechanisms actually cause the flickering -- and a slower quasi-periodic oscillation (QPO) -- in accretion disks surrounding black holes and neutron stars remains a topic of much research."
The astronomer Fred Hoyle once wrote of the herd mentality in his profession: “The trouble with conformity is that the process has strong positive feedback. The baaing starts up at a volume low enough to permit stronger-minded animals to think for themselves without too much trouble. Progressively, however, we break down one-by-one, losing all power of sensible judgement, to the point where we can do nothing but add our own baaing to the uproar, which eventually rises to such monumental proportions that nothing remains for the flock except the butcher's shop.”
Scientists are people and not immune to the madness of crowds. Ideas that appear folly initially may with time and a growing clamour of consensus delude people into believing it is a new "truth." Such is the story of black holes. Two years ago I criticised the theory of black holes and from the correspondence I receive, some scientists and engineers are "recovering their senses slowly, one by one."
Black holes highlight a situation, common today in astrophysics, where the object under investigation cannot be seen directly. This situation is pure heaven for the crowd of mathematical theorists who have hijacked physics from the natural philosophers and experimentalists. The sainted Einstein seems to have initiated the hijacking with that oxymoron, the “thought experiment.” But problems arise when thoughts are governed by a limited set of beliefs or dogmas and unchecked by direct observation or experiment. The result can be – and generally is – science fiction. University libraries and popular science magazines are full of it at the start of this new millennium.
The eminent theoretical physicist Paul Dirac exemplifies the mathematical theorist. He said, "I like to play about with equations, just looking for beautiful mathematical relations which maybe don't have any physical meaning at all. Sometimes they do." I have heard many physicists eulogize the exquisiteness of mathematical expressions. Are we in danger of losing the plot? Unfortunately the subjective beauty of an equation gives no clue to the objective correctness of any physical meaning it may have. If mathematics is an art, where are the art critics? After all, it is they who are responsible for discerning the relationships between artistic expression and experiential reality. Simply broadcasting the subjective visions of mathematical experts may foster only "extraordinary popular delusions."
The central dogma of astrophysics requires the puny force of gravity to generate stars and galaxies. So very small and powerful sources of radiation in deep space require almost infinite concentrations of mass to provide the gravitational force to drive them. The mathematics says so, so it must be true. But it is equivalent to the schoolboy howler of dividing by zero. A near infinite concentration of mass involves speculative physics that cannot be tested in the laboratory. Taken to its extreme — the black hole, which swallows even light — such a concentration swallows commonsense as well. Even Eddington, who produced the gravitational model of stars that inspired Chandrasekhar (who originated the black hole idea), could not swallow it. "A reductio ad absurdum,” he called it. "I think there should be a law of nature to prevent a star from behaving in this absurd way." There is a law, but Eddington himself obscured the simple answer with his “dogmatically correct” gravitational model of stars.
In this situation, of course, guesswork has free reign. Research becomes purely theoretical, engaged in adjusting sacrosanct theory to accommodate anomalous findings, not experimental, seeking to discover patterns of order in the phenomena. And modern computing power encourages playing with theoretical models. But the success of this approach relies on the correct choice of physical model. The most stringent requirement of the model is that it suggest tests and successfully predict the outcomes. Also it is preferable to have one or more different models that are subject to falsification by observations. The black hole model fulfils neither of these criteria. It is a solitary, non-predictive model that has difficulty even explaining the jets emitted by black holes. After all, black holes are supposed to "suck," not "blow." The black hole model has always needed patching up, so it has always been "a topic of much research."
Now we have a report of rapidly flickering light from a black hole.
The simple mechanical lighthouse model, of something many times heavier than the Sun and rotating in milliseconds, is applied (and it isn't clear what generates the narrow beam of radiation). However, to put 450 flashes per second into perspective, that's a 27,000 rpm lighthouse! "I think there should be a law of nature to prevent a star from behaving in this absurd way."
There is a kind of ridiculous inevitability about the progression of such an absurd idea as the black hole. As soon as you begin dealing with infinities you can "prove black is white and white is black and go out and get yourself killed on a pedestrian crossing," as Douglas Adams expressed it. And as if to parody a parody, the black hole has been variously described as black, white, or even pink. The truly mind boggling thing is that the numerous experts can't see the absurdity. And no investigative reporter has called attention to the fact that the emperors of science have no clothes.
Mackay was spot on in 1852 when he wrote, "Men, it has been well said, think in herds; it will be seen that they go mad in herds." It is a fundamental caution against academic hubris that is sorely missing in university curricula. It amplifies the hollow ring of the claim that science is logical and self-correcting. History shows that many major changes in science have had to wait upon "eminent outsiders." Bernard Newgrosh describes these people as an "interesting and important group of people who earn their living in one field whilst undertaking a hobby or other leisure study in a quite different discipline. Their amateur deliberations often result in crucial groundbreaking developments. Many of the laws of science can be credited to these people, also the foundation of new disciplines. This select band has had ideas which were truly new, momentous in the history of science."
Newgrosh continues, "It is a curious fact that almost none of these outsiders had any qualification or academic background in the discipline in which they shone - indeed many were entirely self-taught. Some are not all that well known, having just the single claim to fame but others are polymaths of astonishing intellectual calibre. I am going to call this group 'the eminent outsiders'."
The Eminent Outsider
• Occupation unrelated to discipline of achievement
• Work on hobby or other outside interest leads to discovery
• Initially purely amateur researches, etc.
• Entirely unqualified in discipline of hobby study
• Makes fundamental discoveries
Some examples of eminent outsiders are Hooke, Leibniz, Ben Franklin, Lavoisier, Priestley, Coulomb, Herschel, Young, Fresnel, Carnot, Lyell, Faraday, Ohm, Darwin, Pasteur, Westinghouse, Edison, Bell, and Einstein.
When a discipline is as far off the beam as astrophysics, the field is wide open for eminent outsiders. There are a number who will be recognized in future. The expertise they have in common is electrical engineering and/or experimental plasma science. That should be no surprise since we live in an electric universe.
They include:
• Charles-Edouard Guillaime (1883–1936), Nobel Laureate 1920.
• Kristian Birkeland (1867–1917), Nobel Prize nominee, 1917.
• Hannes Alfvén (1908–1995). 1970 Nobel Laureate for Physics.
• Irving Langmuir. 1932 Nobel Laureate for Chemistry.
• Anthony Peratt, Alfvén's student and author of Physics of the Plasma Universe.
Healy and Peratt have studied the detail of signals from those other super-rotators – pulsars – and have concluded, "[T]he source of the radiant energy may not be contained within the pulsar, but may instead derive either from the pulsar's interaction with its environment or by energy supplied by an external circuit.… [O]ur results support the 'planetary magnetosphere' view, where the extent of the magnetosphere, not emission points on a rotating surface, determines the pulsar emission." In other words, no whirling, super-condensed neutron star is required.
Plasmas transfer energy over great distances to smaller regions where it may be periodically or catastrophically released. Peratt explains the flickering of electromagnetic radiation: "The flickering of a light in Los Angeles does not mean that the supply source, a waterfall or hydroelectric dam in the Pacific Northwest, has abruptly changed dimensions or any other physical property. The flickering comes from electrical changes at the observed load or radiative source, such as the formation of instabilities or virtual anodes or cathodes in charged particle beams that are orders of magnitude smaller than the supply. Bizarre and interesting non-physical interpretations are obtained if the flickering light is interpreted by a distant observer to be both the source and supply."
Black holes and neutron stars can certainly be classified as "bizarre and non-physical" objects. It is commonsense electrical engineering to declare them non-existent. In that case the research funds currently being poured into investigation of black holes, pulsars and gamma-ray bursters is being wasted on astrophysicists and particle physicists. Rather than fritter away further decades waiting for them to "recover their senses slowly, and one by one" we should immediately fund experimental plasma cosmology under the auspices of the IEEE. That way we may at last escape a century of "delusion and madness."
Why neutron stars are impossible
By Don Scott
http://www.electric-cosmos.org/hrdiagr.htm
The concept of the "neutron star" was a baseless invention. It was proposed because only such a dense material could make up a star that could stand those outrageously high rotation speeds.
But, one of the basic rules of nuclear chemistry is the "zone of stability". This is the observation that if we add neutrons to the nucleus of any atom, we need to add an almost proportional number of protons (and their accompanying electrons) to maintain a stable nucleus. In fact, it seems that when we consider all the natural elements (and the heavy man made elements as well), there is a requirement that in order to hold a group of neutrons together in a nucleus, a certain number of proton-electron pairs are required.
The stable nuclei of the lighter elements contain approximately equal numbers of neutrons and protons, a neutron/proton ratio of 1. The heavier nuclei contain a few more neutrons than protons, but the limit seems to be 1.5 neutrons per proton. Nuclei that differ significantly from this ratio SPONTANEOUSLY UNDERGO RADIOACTIVE TRANSFORMATIONS that tend to bring their compositions into or closer to this ratio.
Flying in the face of this fact, mainstream astrophysicists continue to postulate the existence of stars made up of solid material consisting only of neutrons, "Neutronium". This is yet one more example of Fairie Dust entities fantasized by astrophysicists to explain otherwise inexplicable observations. The "neutron star" is simply yet another fantasy conjured up, this time, in order to avoid confronting the idea that pulsar discharges are electrical phenomena. A proton-free nucleus or "charge free" atom made up of only neutrons has never been synthesized in any laboratory nor can it ever be. In fact, a web search on the word "neutronium" will produce only references to a computer game not to any real, scientific discussion or description. Lone neutrons decay into proton - electron pairs in less than 14 minutes; atom-like collections of two or more neutrons will fly apart almost instantaneously.
That astrophysicists feel free to postulate and then quickly accept as fact the existence of such preposterous entities provides deep insight into the present state of their science.
The optical surface of the Sun (the photosphere) is known to have a temperature of approximately 6,000 K. Above it lies the solar corona at a temperature of 1,000,000 K. The high temperature of the corona shows that it is heated by something other than direct heat conduction from the photosphere.It is thought that the energy necessary to heat the corona is provided by turbulent motion in the convection zone below the photosphere, and two main mechanisms have been proposed to explain coronal heating. The first is wave heating, in which sound, gravitational and magnetohydrodynamic waves are produced by turbulence in the convection zone. These waves travel upward and dissipate in the corona, depositing their energy in the ambient gas in the form of heat. The other is magnetic heating, in which magnetic energy is continuously built up by photospheric motion and released through magnetic reconnection in the form of large solar flares and myriad similar but smaller events.[17]
Currently, it is unclear whether waves are an efficient heating mechanism. All waves except Alfvén waves have been found to dissipate or refract before reaching the corona.[18] In addition, Alfvén waves do not easily dissipate in the corona. Current research focus has therefore shifted towards flare heating mechanisms. One possible candidate to explain coronal heating is continuous flaring at small scales,[19] but this remains an open topic of investigation.
lalonde ha scritto:
Dire che le temperature delle stelle aumentano dirigendosi verso il nucleo è parecchio azzardato. La corona solare, ovvero la parte esterna alla superficie raggiunge la temperatura di 1.000.000 milione di gradi, mentre la superficie solare raggiunge mediamente i 6000 k.
citazione da Wikipedia
Citazione:The optical surface of the Sun (the photosphere) is known to have a temperature of approximately 6,000 K. Above it lies the solar corona at a temperature of 1,000,000 K. The high temperature of the corona shows that it is heated by something other than direct heat conduction from the photosphere.It is thought that the energy necessary to heat the corona is provided by turbulent motion in the convection zone below the photosphere, and two main mechanisms have been proposed to explain coronal heating. The first is wave heating, in which sound, gravitational and magnetohydrodynamic waves are produced by turbulence in the convection zone. These waves travel upward and dissipate in the corona, depositing their energy in the ambient gas in the form of heat. The other is magnetic heating, in which magnetic energy is continuously built up by photospheric motion and released through magnetic reconnection in the form of large solar flares and myriad similar but smaller events.[17]
Currently, it is unclear whether waves are an efficient heating mechanism. All waves except Alfvén waves have been found to dissipate or refract before reaching the corona.[18] In addition, Alfvén waves do not easily dissipate in the corona. Current research focus has therefore shifted towards flare heating mechanisms. One possible candidate to explain coronal heating is continuous flaring at small scales,[19] but this remains an open topic of investigation.
Per spiegare tutto ciò i fisici si stanno arrampicando sugli specchi....direi che è un argomento cruciale. La nostra cara e vecchia(?) stella....quanto poco ne sappiamo^^
Edit: Scusa Ivan, ho visto solo ora che avevi già postato qualcosa a proposito. Sarebbe interessante una discussione sulla teoria dell'universo elettrico....se ne vedrebbero delle belle^^
Strange Star or Strange Science?
Nowhere is the gravitational paradigm of cosmology shown to exhibit more strangeness than in compact high energy phenomena in deep space. A report in the journal Nature of 15 November proposes that a recently discovered star "is made of an exotic stuff called 'strange matter', never yet seen on Earth". In other words, it may be a "strange star". This bizarre suggestion comes out of the mathematics describing stars that generate rapid pulses of radiation, commonly called "pulsars". The x-ray pulses are thought to be due to a rotating beam of x-rays that flashes toward the Earth once per revolution like a cosmic lighthouse.
This seemingly simple model began to show signs of strain many years ago when the first millisecond pulsar was discovered. In order to flash (rotate) several times a second a pulsar would need to be very compact indeed, only a few kilometres in diameter. But to generate x-rays gravitationally requires an extreme concentration of matter to accelerate particles to a sufficiently high energy so that when they strike the star x-rays are produced. The only objects that theoretically meet that requirement are neutron stars and black holes. Both kinds of object are well outside our experience.
The discovery now of an x-ray pulsar SAX J1808.4-3658 (J1808 for short), located in the constellation of Sagittarius, that flashes every 2.5 thousandths of a second (that is 24,000 RPM!) goes way beyond the red-line even for a neutron star. So another ad hoc requirement is added to the already long list - this pulsar must be composed of something even more dense than packed neutrons - strange matter!
When astrophysicists are having difficulty with their models they traditionally turn for rescue to the nuclear physicists. (They were called in to explain away the missing solar neutrinos). The news report goes on: "The most fundamental building blocks of nuclear matter are thought to be particles called quarks. The 'regular' nuclear particles or 'nucleons' - protons and neutrons - are composed of 'up' and 'down' quarks: two up quarks and a down quark make one proton, while a neutron consists of two downs and an up. But there are at least four other, more exotic, kinds of quark, amongst them the so-called 'strange' quark. In nucleons, quarks are supposed to exist in inseparable groups of three, which is why no one has ever seen an isolated quark. But at extremely high densities of matter, quarks may become uncoupled or 'deconfined'. 'Strange matter' is a melange of deconfined up, down and strange quarks. Physicists are hoping that the new particle colliders currently under construction, such as the Larger Hadron Collider at CERN in Geneva, will create conditions extreme enough to break quarks free. But the Universe may have got there first. X.-D. Li of Nanjing University, China, and colleagues' suggestion that J1808 is a strange star follows a small number of similar proposals for other astrophysical objects that emit bursts of X-rays. The X-ray bursts from these objects are signs of violent activity of a sort that becomes possible only when matter is pushed to extremes."
I think J R Saul highlighted the language problem we are seeing here when he wrote, "Ten geographers who think the world is flat will tend to reinforce each other's errors. If they have a private dialect in which to do this, it becomes impossible for outsiders to disagree with them. Only a sailor can set them straight. The last person they want to meet is someone who, freed from the constraints of expertise, has sailed around the world." J R Saul, Voltaire's Bastards.
The Nobel Laureate, Irving Langmuir, coined the term "pathological science" for "the science of things that aren't so".
Two key symptoms of such science are:
(1) the resort to fantastic theories contrary to our experience, and
(2) the use of ad-hoc requirements to save the appearances.
(ivan'note: vi ricorda nulla ?)
If we apply these criteria, two disciplines that share line honours for pathological or strange science are cosmology and particle physics. They both deal with unseen objects - neutron stars, black holes, quarks, etc. They both produce fantastic ad-hoc requirements to explain new discoveries - dark matter, super-heavy objects and exotic particles. They cross-infect each other with their theoretical requirements both to save appearances and convince governments to spend large sums of research money for super-colliders to replay bits of a hypothetical Big Bang, or to build gravity-wave telescopes when we have no proof such waves exist. The above report brings such strange science sharply into focus.
It is not ordinary matter, but scientific models that are being pushed to extremes. Einstein warned: "Most mistakes in philosophy and logic occur because the human mind is apt to take the symbol for reality". Neutron stars and quarks have never been seen. They are derived from mathematical symbols. Let's take quarks first. There is little to suggest that any of the shrapnel from high energy colliders exists in normal matter. If enormous energy is spent in shattering a proton to unlock the hypothetical quarks then the energy itself may manifest as particles that don't play any part in ordinary matter. Flying a 747 into a mountainside and picking over the ruins is not the best way of finding out how an aircraft works. Suggesting that a star can be composed stably of unobserved particles simply because a theory of invisible, super-heavy objects demands it is asking too much!
Here are some of the many unstated assumptions underpinning the X-ray pulsar model:
(my comments are in italics)
1. It is assumed that the physics of neutral matter and ideal gases on Earth can be used to explain the operation of the glowing balls of plasma we call stars.
99.999% of the universe is made of plasma. It is not necessarily electrically neutral and does not behave like an ideal gas.
2. It is assumed that all interstellar plasma is mostly an ionized, uncharged, superconducting gas that can trap and carry magnetic fields.
Plasma is not a superconductor so magnetic fields cannot be trapped in it. The origin of the magnetic fields is not clear from standard theory. The Electric Universe proposes that magnetic fields and plasma filaments in space are formed by electrical currents in charged plasma. (No book on astronomy mentions electrical effects).
3. It is assumed that we understand how our Sun and other stars shine, evolve, and someday die or form neutron stars.
We do not understand the Sun's magnetic field, the hot corona, solar wind, solar cycle, x-ray variability, coronal mass ejections, sunspots, low neutrino count, etc., etc.
4. It is assumed that we understand what causes a supernova explosion.
The number of ad hoc assumptions required for a mechanical explosion following a sudden stellar implosion results in a highly unlikely explanation. SN1987A showed that such explosions are not spherically symmetrical.
5. It is assumed that a supernova can "squeeze" stellar protons and electrons together to form neutrons.
A first-order wild conjecture. The model incorporates many unproven assumptions about the unseen internal structure of stars. If the implosion is not spherically symmetrical there may be insufficient "squeeze" to force protons and electrons to merge, even if that were possible. No account is taken of electrical effects. Our own Sun with a mean density only slightly above that of pure hydrogen shows that electrostatic forces are at work within stars to offset compression forces.
6. It is assumed that it is possible to form a stable neutron star.
When not associated with protons in a nucleus, neutrons decay into protons and electrons in a few minutes. Atomic nuclei with too many neutrons are unstable. If it were possible to form a neutron star, why should it be stable?
7. It is assumed that a supernova can further squeeze neutrons until they "pop their quarks".
A second-order wild conjecture.
8. It is assumed that it is possible to have a stable massive object composed of quarks.
A third-order wild conjecture based on the pathologies of both astrophysics and nuclear physics. It is an unseen object composed of unseen matter.
9. It is assumed that a neutron star can convert the energy of infalling matter into tightly collimated, pulsed x-ray beams.
It is difficult to imagine a more unlikely way of achieving this effect.
10. It is assumed that a spinning object is required to cause the pulsations.
Only required in a purely mechanical model.
11. It is assumed that Nature overlooks the normal (and infinitely easier) method of creating x-rays by accelerating electrons in an electric field.
12. It is assumed that Nature overlooks the simplest way of creating pulsed radiation by a charge-discharge relaxation oscillator cycle (where electric charge builds up slowly until a threshold is reached and a sudden discharge occurs).
13. It is assumed that Nature ignores the simplest way of creating a highly collimated x-ray beam and particle jet (if one is required from the observations) by the use of the plasma focus effect.
Is this science or science-fiction?
The Electric Universe model assumes that Nature knows best. It does not require strange matter or a strange star. The x-ray pulses are caused by regular electric discharges between two or more orbiting, normally constituted, electrically charged bodies. It is a manifestation of a periodic arc instead of a spinning star. If beaming of the radiation is occurring then that should be verifiable here on Earth in the lab by studying the plasma focus device.
The Electric Universe model lets go of the Newtonian dogma that gravity is the driving force in the cosmos. It allows for the possibility that the fundamental characteristic of normal matter - its electric charge - plays the most significant role. So if gravity wave telescopes detect anything at all, it won't be gravity waves from super-heavy objects. And particle physicists who are trying to work out how the universe was constructed from strange matter early in the Big Bang are wasting their time. The astronomer Halton Arp, author of the Atlas of Peculiar Galaxies, has conclusively disproven the theory of an expanding universe and so knocked out the foundation of the Big Bang theory.
Meanwhile the plasma physicists and electrical engineers are waiting in the wings for those astro-and nuclear-physicists parading their strange science in public to get off the stage. It would be entertaining if it weren't so serious. But it is costing us dearly and holding up real progress.
ora, visto che al suolo la tmeperatura è di 25°C dobbiamo convenire che essa diminuisce con l'altezza e quindi il nucleo del nostro pianeta è freddissimo??
certo che no!
stesso dicasi per la corona solare
ivan ha scritto:
Citazione:
ora, visto che al suolo la tmeperatura è di 25°C dobbiamo convenire che essa diminuisce con l'altezza e quindi il nucleo del nostro pianeta è freddissimo??
certo che no!
stesso dicasi per la corona solare
A parer tuo, chi la scalda la corona solare ?
The temperature of the corona is several million kelvin. While no complete theory yet exists to account for the temperature of the corona, at least some of its heat is known to be from magnetic reconnection.
The Myth of Magnetic Reconnection
Electrical engineers and plasma cosmologists will tell you that magnetic reconnection is one of the most contradictory ideas that astronomers ever derived from the mistaken belief that there are no electric currents in space.
Astronomers today are taking pictures of something they call “magnetic reconnection” on the Sun, and space probes are measuring something else in the Earth's magnetosphere that has also been given the same name. If you ask a plasma cosmologist about these, he'll tell you that the astronomers don't know what they're talking about. They're looking at well-understood plasma phenomena, exploding double layers and electric discharge, not magnetic reconnection.
Which side will triumph? Here's how it's shaping up. Now that astronomers are looking at real phenomena rather than elegant equations, they realize that their equations aren't as predictive as they had hoped. The magnetic reconnection equations called for a slow discharge of energy lasting for years, but the solar flares discharge in minutes with much more energy than expected. But astronomers have also noticed that whenever magnetic reconnection happens, there seem to be regions of electron-depleted space associated with it [plasma cosmologists call them electric currents.] The electron-depleted atoms are traveling at speeds of up to 1000 km/sec [which plasma cosmologists recognize as one of the "characteristic velocities" of plasma in the lab.] And astronomers find that during the magnetic reconnection process, a two-layer flow of particles is created that speeds the release of energy [plasma cosmologists call them double layers.]
The only problem astronomers still need to solve is why so much more energy than they were expecting is produced by the process. Hannés Alfvén could help them here: In the mid-1960's, he was called by the Swedish Power Company to solve a similar problem on a more down-to-Earth scale. The company was using large rectifiers to convert electrical power from AC to DC for easier transport from the generators in the north to the cities in the south. But every once in a while the plasma in the rectifier would explode, causing considerable damage. The problem turned out to be exploding double layers, like those found in "magnetic reconnection" on the Sun. The explosions expended more energy than was contained by the plasma in the rectifier because the energy from the whole length of the circuit flowed back into the break. In Sweden, this was over 600 miles of electric wires. On the Sun -- well, we don't know yet how long those circuits are.
The astronomers will no doubt solve the problem of too much energy released by magnetic reconnection, and the answer will no doubt depend on the dimensions of the "electron-depleted regions." But the question for historians is this: who will be remembered? Will this still be called magnetic reconnection (although it hardly resembles the original theory at all)? Will its discovery be credited to early 21st century astronomers? Or will history remember that plasma researchers like Jacobson and Carlqvist were explaining solar flares as exploded double layers 50 years ago?
Messaggio orinale: https://old.luogocomune.net/site/newbb/viewtopic.php?forum=54&topic_id=2166