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NEUTRINOS, NEUTRONS and NEUTRON STARS

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Majeston
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NEUTRINOS, NEUTRONS and NEUTRON STARS
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Because of the mandatory restrictions imposed on the revelators (1109), the science and cosmology of The Urantia Book is at the approximate level of current human knowledge for the mid-1930's. It also contains some statements that were prophetic at that time because the mandate allowed the revelators to supply vital information to fill gaps in our otherwise earned knowledge. One such gap-filler may have been:

"In large suns when hydrogen is exhausted and gravity contraction ensures, and such a body is not sufficiently opaque to retain the internal pressure of support for the outer gas regions, then a sudden collapse occurs.  The gravity-electric changes give origin to vast quantities of tiny particles devoid of electric potential, and such particles readily escape from the solar interior thus bringing about the collapse of a gigantic sun within a few days."(464)

No tiny particles devoid of electric potential that could escape readily from the interior of a collapsing star were known to exist in 1934. In fact, the reality of such particles were not confirmed until 1956, one year after the publication of The Urantia Book. The existence of particles that might have such properties had been put forward as a suggestion by Wolfgang Pauli in 1932, because studies on radioactive beta decay of atoms had indicated that a neutron could decay to a proton and an electron, but measurements had shown that the combined mass energy of the electron and proton did not add up with that of the neutron. To account for the missing energy, Pauli suggested a little neutral particle was emitted, and then, on the same day, while lunching with the eminent astrophysicist Walter Baade, Pauli commented that he had done the worst thing a theoretical physicist could possibly do, he had proposed a particle that could never be discovered because it had no properties. Not long after, the great Enrico Fermi took up Pauli's idea and attempted to publish a paper on the subject in the prestigious science journal "Nature." The editors rejected Fermi's paper on the grounds that it was too speculative. This was in 1933, the year before receipt of the relevant Urantia Paper.

An interesting thing to note is The Urantia Book statement that tiny particles devoid of electric potential would be released in vast quantities during the collapse of the star. If, in 1934, an author other than a knowledgeable particle physicist was prophesying about the formation of a neutron star (a wildly speculative proposal from Zwicky and Baade in the early 1930's), then surely that author would have been thinking about the reversal of beta decay in which a proton, an electron and Pauli's little neutral particle would be squeezed together to form a neutron.

Radioactive beta decay can be written...
1. neutron ----> proton + electron + LNP
where LNP stands for little neutral particle.  Hence the reverse should be:
2. LNP + electron + proton---->neutron

For this to occur an electron and a proton have to be compressed to form a neutron but somehow they would have to add a little neutral particle in order to make up for the missing mass-energy. Thus, in terms of available speculative scientific concepts in 1934, The Urantia Book appears to have put things back to front, it has predicted a vast release of LNP's, when the reversal of radioactive beta decay would appear to demand that LNPs should disappear.

The idea of a neutron star was considered to be highly speculative right up until 1967. Most astronomers believed that stars of average size, like our sun, up to stars that are very massive, finished their lives as white dwarfs. The theoretical properties of neutron stars were just too preposterous; for example, a thimble full would weigh about 100 million tonnes. A favored alternative proposal was that large stars were presumed to blow off their surplus mass a piece at a time until they got below the Chandrasekhar limit of 1.4 solar masses, when they could retire as respectable white dwarfs. This process did not entail the release of vast quantities of tiny particles devoid of electric potential that accompany star collapse as described in the cited Urantia Book quotation.

Distinguished Russian astrophysicist, Igor Novikov, has written, "Apparently no searches in earnest for neutron stars or black holes were attempted by astronomers before the 1960s. It was tacitly assumed that these objects were far too eccentric and most probably were the fruits of theorists wishful thinking. Preferably, one avoided speaking about them. Sometimes they were mentioned vaguely with a remark yes, they could be formed, but in all likelihood this had never happened. At any rate, if they existed, then they could not be detected."
    Acceptance of the existence of neutron stars gained ground slowly with discoveries accompanying the development of radio and x-ray astronomy. The Crab nebula played a central role as ideas about it emerged in the decade, 1950-1960. Originally observed as an explosion in the sky by Chinese astronomers in 1054, interest in the Crab nebula increased when, in 1958, Walter Baade reported visual observations suggesting moving ripples in its nebulosity. When sensitive electronic devices replaced  the photographic plate as a means of detection, the oscillation frequency of what was thought to be a white dwarf star at the center of the Crab nebula turned out to be about 30 times per second.

For a white dwarf star with a diameter in the order of 1000 km, a rotation rate of even once per second would cause it to disintegrate due to centrifugal forces. Hence, this remarkably short pulsation period implied that the object responsible for the light variations must be very much smaller than a white dwarf, and the only possible contender for such properties appeared to be a neutron star. Final acceptance came with pictures of the center of the Crab nebula beamed back to earth by the orbiting Einstein X-ray observatory in 1967. These confirmed and amplified the evidence obtained by prior observations made with both light and radio telescopes.

next column>
   
The reversal of beta-decay, as depicted in (2) above, involves a triple collision, an extremely improbable event, unless two of the components combine in a meta-stable state--a fact not likely to be obvious to a non-expert observer which also indicates that the author(s) of the Urantia Paper was highly knowledgeable in this field.

The probable evolutionary course of collapse of massive stars has only been elucidated since the advent of fast computers. Such stars begin life composed mainly of hydrogen gas that burns to form helium. The nuclear energy released in this way holds off the gravitational urge to collapse. With the hydrogen in the central core exhausted, the core begins to shrink and heat up, making the outer layers expand. With the rise in temperature in the core, helium fuses to give carbon and oxygen, while the hydrogen around the core continues to make helium. At this stage the star expands to become a red giant.

After exhaustion of helium at the core, gravitational contraction again occurs and the rise in temperature permits carbon to burn to yield neon, sodium, and magnesium, after which the star begins to shrink to become a blue giant. Neon and oxygen burning follow. Finally silicon and sulphur, the products from burning of oxygen, ignite to produce iron. Iron nuclei cannot release energy on fusing together, hence with the exhaustion of its fuel source, the furnace at the center of the star goes out. Nothing can now slow the onslaught of gravitational collapse, and when the iron core reaches a critical mass of 1.4 times the mass of our sun, and the diameter of the star is now about half that of the earth, the star's fate is sealed.

Within a few tenths of a second, the iron ball collapses to about 50 kilometers across and then the collapse is halted as its density approaches that of the atomic nucleus and the protons and neutrons cannot be further squeezed together. The halting of the collapse sends a tremendous shock wave back  through the outer region of the core.

The light we see from our sun comes only from its outer surface layer. However, the energy that fuels the sunlight (and life on earth) originates from the hot, dense thermonuclear furnace at the Sun's core. Though sunlight takes only about eight minutes to travel from the sun to earth, the energy from the sun's core that gives rise to this sunlight takes in the order of a million years to diffuse from the core to the surface. In other words, a sun (or star) is relatively "opaque" (as per The Urantia Book, p.464) to the energy diffusing from its thermonuclear core to its surface, hence it supplies the pressure necessary to prevent gravitational collapse. But this is not true of the little neutral particles, known since the mid 1930's by the name "neutrinos." These particles are so tiny and unreactive that their passage from our sun's core to its exterior takes only about 3 seconds.

It is because neutrinos can escape so readily that they have a critical role in bringing about the star's sudden death and the ensuing explosion. Neutrinos are formed in a variety of ways, many as neutrino-antineutrino pairs from highly energetic gamma rays and others arise as the compressed protons capture an electron (or expel a positron) to become neutrons, a reaction that is accompanied by the release of a neutrino. Something in the order of 1057 electron neutrinos are released in this way. Neutral current reactions from Zo particles of the weak force also contribute electron neutrinos along with the 'heavy' muon and tau neutrinos.

Together, these neutrinos constitute a "vast quantity of tiny particles devoid of electric potential" that readily escape from the star's interior. Calculations indicate that they carry ninety-nine percent of the energy released in the final supernova explosion. The gigantic flash of light that accompanies the explosion accounts for only a part of the remaining one percent! Although the bulk of the neutrinos and anti-neutrinos are released during the final explosion, they are also produced at the enormous temperatures reached by the inner core during final stages of contraction.

The opportunity to confirm the release of the neutrinos postulated to accompany the spectacular death of a giant star came in 1987 when a supernova explosion, visible to the naked eye, occurred in the Cloud of Magellan that neighbors our Milky Way galaxy. Calculations indicated that this supernova, dubbed SN1987A, should give rise to a neutrino burst at a density of 50 billion per square centimeter when it finally reached the earth, even though expanding as a spherical 'surface' originating at a distance 170,000 light years away. This neutrino burst was observed in the huge neutrino detectors at Kamiokande in Japan and at Fairport, Ohio, in the USA. lasting for a period of just 12 seconds, and confirming the computer simulations that indicated they should diffuse through the dense core relatively slowly. From the average energy and the number of 'hits' by the neutrinos in the detectors, it was possible to estimate that the energy released by SN1987 amounted to 2-3 x 1053 ergs. This is equal to the calculated gravitational binding energy that would be released by the collapse of a core of about 1.5 solar masses to a neutron star. Thus SN1987A provided a remarkable confirmation of the general picture of neutron star formation developed over the last fifty years. Importantly, it also confirmed that The Urantia Book had its facts right long before the concept of neutrino-spawning neutron stars achieved respectability...

------------------------------------------------------------------------

References:

Hoyle, F., and J. Narlikar. "The Physics Astronomy Frontier." (W.H. Freeman & Co. San Francisco, 1980.)
Novikov, I. "Black Holes and the Universe." (Cambridge University Press, 1990)
Sutton, C.  "Spaceship Neutrino." (Cambridge University Press, Cambridge, 1992)

------------------------------------------------------------------------

Addendum to "Neutrinos, Neutrons, and Neutron stars."

"In large suns when hydrogen is exhausted and gravity contraction ensues, and such a body is not sufficiently opaque to retain the internal pressure of support for the outer gas regions, then a sudden collapse occurs. The gravity-electric changes give origin to vast quantities of tiny particles devoid of electric potential, and such particles readily escape from the solar interior thus bringing about the collapse of a gigantic sun within a few days." (p. 464) For the mid-thirties that was quite a statement. These tiny particles that we now call neutrinos were entirely speculative in the early 1930's and were required to account for the missing mass-energy of beta radioactive decay. Hypotheses on the possible origins of the Urantia Paper's statement on solar collapse

In the early 1930's, the idea that supernova explosions could occur and result in the formation of neutron stars was extensively publicized by Fritz Zwicky of the California Institute of Technology (Caltec) who worked in Professor Millikan's dept. For a period during the mid-thirties, Zwicky was also at the University of Chicago. Dr. Sadler is said to have known Millikan. So alternative possibilities for the origin of The Urantia Book quote above could be:

1. The revelators followed their mandate and used a human source of information about supernovae, possibly Zwicky.

2. Dr Sadler had learned about the tiny particles devoid of electric potential from either Zwicky, Millikan, or some other knowledgeable person and incorporated it into The Urantia Book.

3. It is information supplied to fill missing gaps in otherwise earned knowledge as permitted in the mandate. (1110)

Zwicky had the reputation of being a brilliant scientist but given to much wild speculation, some of which turned out to be correct. A paper published by Zwicky and Baade in 1934 proposed that neutron stars would be formed in stellar collapse and that 10% of the mass would be lost in the process. (Phys. Reviews. Vol. 45)

In Black Holes and Time Warps: Einstein's Outrageous Legacy (Picador, London, 1994), a book that covers the work and thought of this period in detail, K.S. Thorne, Feynman Professor of Theoretical Physics at Caltec, writes: "In the early 1930's, Fritz Zwicky and Walter Baade joined forces to study novae, stars that suddenly flare up and shine 10,000 times more brightly than before. Baade was aware of tentative evidence that, besides ordinary novae, there existed superluminous novae. These were roughly of the same brightness but since they were thought to occur in nebulae far out beyond our Milky Way, they must signal events of extraordinary magnitude. Baade collected data on six such novae that had occurred during the current century.

"As Baade and Zwicky struggled to understand supernovae, James Chadwick, in 1932, reported the discovery of the neutron. This was just what Zwicky required to calculate that if a star could be made to implode until it reached the density of the atomic nucleus, it might transform into a gas of neutrons, reduce its radius to a shrunken core, and, in the process, lose about 10% of its mass. The energy equivalent of the mass loss would then supply the explosive force to power a supernova.

"Zwicky did not know what might initiate implosion nor how the core might behave as it imploded. Hence he could not estimate how long the process might take—is it a slow contraction or a high-speed implosion? Details of this process were not worked out until the 1960's and later.

Zwicky believed cosmic rays accounted for the mass-energy loss in supernova explosions

"At this time (1932-33), cosmic rays were receiving much attention and Zwicky, with his love of extremes, managed to convince himself that most of the cosmic rays (correctly) were coming from outside our solar system and (incorrectly) that most were from far outside our Milky Way galaxy—indeed from the most distant reaches of the universe—and he then convinced himself (roughly correctly) that the total energy carried by all of the universe's cosmic rays was about the same as the total energy released by supernovae throughout the universe. The conclusion was obvious to Zwicky. Cosmic rays must be made in supernova explosions." Baade and Zwicky's paper of 1934 asserted unequivocally the existence of supernovae as a distinct class of astronomical objects different from ordinary novae. It estimated the total energy released (10% of solar mass), and proposed that the core would consist of neutrons, a speculation that was not accepted as theoretically viable until 1939 nor verified observationally until 1967 with the discovery of pulsars—spinning, magnetized neutron stars inside the exploding gas of ancient supernovae. Information, extracted from Thorne's recent book, indicates that Zwicky knew nothing about the possible role of "little neutral particles" in the implosion of a neutron star, but rather that he attributed the entire mass-energy loss to cosmic rays. So, if not from Zwicky, what then is the human origin of The Urantia Book's statement that the neutrinos escaping from its interior bring about the collapse of the imploding star? (Current estimates attribute about 99% of the energy of a supernova explosion to being carried off by the neutrinos).

In his book, Thorne further states: "Astronomers in the 1930's responded enthusiastically to the Baade-Zwicky concept of a supernova, but treated Zwicky's neutron star and cosmic ray ideas with disdain...In fact it is clear to me from a detailed study of Zwicky's writings of the era that he did not understand the laws of physics well enough to be able to substantiate his ideas." This opinion was also held by Robert Oppenheimer who published a set of papers with collaborators Volkoff, Snyder, and Tolman, on Russian physicist Lev Landau's ideas about stellar energy originating from a neutron core at the heart of a star. Oppenheimer ignored Zwicky's speculative proposals, though he must have been familiar with them as he worked about half of each year at Caltec.

The Oppenheimer papers were mainly theoretical in nature and based upon the principles of relativistic physics. In a 1939 paper of Oppenheimer and Snyder, since they had neither the detailed knowledge nor the computational machinery to formulate a realistic model of a collapsing star, they took as their starting point a star that was precisely spherical, non-spinning, non-radiating, of uniform density and no internal pressure. Their conclusions included that, for an observer from a static external reference frame, the implosion of a massive star freezes at the critical circumference of the star (i.e. where gravity becomes so strong that not even light can escape) but, as considered from the reference frame of the star's surface, it may continue to implode (ultimately to a Schwarzschild singularity—the term "black hole" had yet to be invented).

Einstein and Eddington opposed neutron star concept

These Oppenheimer papers, which concluded that either neutron stars or black holes could be the outcome of massive star implosion, were about as far as physicists could go at that time. As a further deterrent to speculation on the fate of imploding massive stars, the most prominent physicist of the time, Albert Einstein, and the doyen of astronomers, Sir Arthur Eddington, both vigorously opposed the concepts involved in stellar collapse beyond the white dwarf stage. Thus the subject appears to have been put on hold coincident with the outbreak of war in 1939. During the 1940's, virtually all capable physicists were occupied with tasks relating to the war effort. Apparently this was not so for Russian-born astronomer-physicist, George Gamow, a professor at Leningrad who had taken up a position at George Washington University in 1934. Gamow conceived the beginning of the Hubble expanding universe as a thermonuclear fireball in which the original stuff of creation was a dense gas of protons, neutrons, electrons, and gamma radiation which transmuted by a chain of nuclear reactions into the variety of elements that make up the world of today. Referring to this work, Overbye4 writes: "In the forties, Gamow and a group of collaborators wrote a series of papers spelling out the details of thermonucleogenesis. Unfortunately their scheme didn't work. Some atomic nuclei were so unstable that they fell apart before they could fuse again into something heavier, thus breaking the element building chain. Gamow's team disbanded in the late 40's, its work ignored and disdained."

Among this work was a paper by Gamow and Schoenfeld that proposed that energy loss from aging stars would be mediated by an efflux of neutrinos. However they also noted that "the neutrinos are still considered as highly hypothetical particles becauseof the failure of all efforts to detect them. Their proposal appears to have been overlooked or ignored until the 1960's.

Conservation of energy "law" under fire

Pauli's suggestion about the necessary existence of the tiny unknown particle devoid of electric potential that we now call the neutrino was made just prior to Chadwick's discovery of the neutron in 1932. The name, neutrino, was suggested by Enrico Fermi. In beta decay, when a neutron breaks down to a proton and an electron, the loss in mass is 0.00029 on the atomic weight scale, approximately the mass of half an electron. In some decay events, the electron gets most of the missing mass-energy in the form of kinetic energy. Since the missing particle must also have kinetic energy it became clear that it must be massless or very close thereto. Many thought it must be massless like the photon and travel with the velocity of light. Although no one wanted to abandon the law of conservation of energy, there was considerable doubt about saving it by means of a particle without charge and probably without mass, a particle that could never be detected and whose sole reason for existence was merely to save a law. [Note: In 1957, the 30-year old law of conservation of parity was shown to be violated during neutrino emission in beta radioactive decay.]

As time went by, the need for the neutrino grew, not only to save the law of conservation of energy, but also conservation of momentum, angular momentum (spin), and lepton number. As knowledge of what it ought to be like grew, and as knowledge accrued from the intense efforts to produce the atom bomb, possible means of detecting this particle began to emerge. In 1953, experiments were begun by a team led by C.L. Cowan and F. Reines.1 Fission reactors were now in existence in which the breakdown of uranium yielded free neutrons that, outside of the atomic nucleus, were unstable and broke down via beta decay to yield a proton, an electron, and, if it existed, the missing particle. The fission reactor chosen at Savannah River, North Carolina was estimated to provide 1,000,000,000,000,000,000 each second. These should be antineutrinos.

Detection of the elusive neutrino

The Cowan and Reines team devised a scheme to feed the antineutrinos from the reactor into a target consisting of water. Each water molecule consists of two hydrogen atoms and one oxygen, and the nuclei of the hydrogen atoms are protons. A scintillator substance was added to the water contained in a series of tanks surrounded by scintillation detectors. If an antineutrino was absorbed by a proton, the expectation was that a neutron and a positron (antielectron) would be formed. In such an environment the positron should collide with an electron within about a millionth of a second, and the two should annihilate with the production of two gamma ray photons shot out in exactly opposite directions. An added refinement was detection of the newly formed neutron which, in the presence of cadmium ions, would immediately be taken into the cadmium nucleus with emission of photons with combined energy of 9 Mev. Detection of this sequence of events would herald the existence of the antineutrino. In 1956 this system was detecting 70 such events per day with the fission reactor operating over and above the background noise with the reactor shut off. It now remained to prove that this particle was not its own antiparticle, as is the case with the photon. This was done by R.R. Davis in 19561, using a system designed specifically to detect expected neutrino properties, but testing for those properties with antineutrinos deriving from a fission reactor. The negative results so obtained provided evidence for there being two different particles. Confirmation of the existence of the neutrino (as distinct from the anti-neutrino) was obtained in 1965 when neutrinos from the sun were detected in huge perchloroethylene tanks placed far underground. Renewal of the search for the neutron star

The subject of the fate of imploding stars re-opened with vigor when both Robert Oppenheimer and John Wheeler, two of the really great names of physics, attended a conference in Brussels in 1958. Oppenheimer believed that his 1939 papers said all that needed to be said about such implosions. Wheeler disagreed, wanting to know what went on beyond the well-established laws of physics.

When Oppenheimer and Snyder did their work in 1939, it had been hopeless to compute the details of the implosion. In the meantime, nuclear weapons design had provided the necessary tools because, to design a bomb, nuclear reactions, pressure effects, shock waves, heat, radiation, and mass ejection had to be taken into account. Wheeler realized that his team had only to rewrite their computer programs so as to simulate implosion rather than explosion. However his hydrogen bomb team had been disbanded and it fell to Stirling Colgate at Livermore, in collaboration with Richard White and Michael May, to do these simulations. Wheeler learned of the results and was largely responsible for generating the enthusiasm to follow this line of research. The term ‘black hole' was coined by Wheeler.

The theoretical basis for supernova explosions is said to have been laid by E. M. Burbidge, G.R. Burbidge, W. A. Fowler, and Fred Hoyle in a 1957 paper2. However, even in Hoyle and Narlikar's text book, The Physics-Astronomy Frontier (1980), no consideration is given to a role for neutrinos in the explosive conduction of energy away from the core of a supernova. In their 1957 paper, Hoyle and his co-workers proposed that when the temperature of an aging massive star rises to about 7 billion degrees K, iron is rapidly converted into helium by a nuclear process that absorbs energy. In meeting the sudden demand for this energy, the core cools rapidly and shrinks catastrophically, implodes in seconds, and the outer envelope crashes into it. As the lighter elements are heated by the implosion they burn so rapidly that the envelope is blasted into space. So, two years after the first publication of The Urantia Book, the most eminent authorities in the field of star evolution make no reference to the "vast quantities of tiny particles devoid of electric potential" that the book says escape from the star interior to bring about its collapse. Instead they invoke the conversion of iron to helium, an energy consuming process now thought not to be of significance.

Following on from the forgotten Gamow and Schoenfeld paper, the next suggestion that neutrinos may have a role in supernovae came from Ph.D. student Hong-Yee Chiu, working under Philip Morrison. Chiu proposed that towards the end of the life of a massive star, the core would reach temperatures of about 3 billion degrees at which electron-positron pairs would be formed and a tiny fraction of these pairs would give rise to neutrino-antineutrino pairs. Chiu speculated that X-rays would be given off by the star for about 1000 years and that the temperature would ultimately reach about 6 billion degrees when an iron core would form at the central region of the star. The flux of neutrino-antineutrino pairs would then be sufficiently great to carry off the explosive energy of the star in a single day. The 1000-year period predicted by Chiu for X-ray emission was reduced to about one year by later workers. Chiu's proposals appear to have been first published in a Ph. D. thesis submitted at Cornell University in 1959. Scattered references to it are made by Philip Morrison3 and by Isaac Asimov1.

No neutral current, no supernova

Dennis Overbye, in his book Lonely Hearts of the Cosmos4 records that, for supernovae, almost all the energy of the inward free fall comes out in the form of neutrinos. The success of this scenario (as proposed by Chiu) depends on a feature of the weak interaction called the neutral currents. Without this, the neutrinos do not supply enough ‘oomph' and theorists had no good explanation for how stars explode. In actuality the existence of the neutral current for the weak interaction was not demonstrated until the mid 1970's.

A 1985 paper (Scientific American) by Bethe and Brown entitled "How a Supernova Explodes" shows that understanding of the important role of the neutrinos was well advanced by that time. These authors attribute this understanding to the computer simulations of W. David Arnett of the University of Chicago and Thomas Weaver and Stanford Woosley of the University of California at Santa Cruz.

In a recent report in Sky and Telescope (August, 1995) it is stated that, during the past decade, computer simulations of supernovae have bogged down at 100 to 150 km from the center and failed to explode. These models were one dimensional. With more computer power becoming available, two dimensional simulations have now been carried out and model supernova explosions produced. The one reported was for a 15 solar mass supernova that winds up as a neutron star. However the authors speculate that at least some 5 to 15 solar mass implosions might wind up as black holes. There is still a long way to go in understanding the details of stellar implosions.

Who dunit? Paring away the alternatives

Referring to our three alternatives to explain how the reference to the role of the tiny uncharged particles in supernova explosions got to be in the Urantia Papers, ostensibly in 1934, our investigation showed that Zwicky is unlikely to have been the source as he firmly believed X-rays, not neutrinos, accounted for the 10% mass loss during the death of the star. Remembering that neutron stars were not demonstrated to exist until 1967, that some of the biggest names in physics and astronomy were totally opposed to the concept of collapsing stars (Einstein, Eddington), and that, well into the 1960's, the majority of astronomers assumed that massive stars shed their bulk piecemeal prior to retiring respectably as white dwarfs, it appears that it would have been a preposterous notion to attempt to support the reality of a revelation by means of speculation about the events occurring in massive star implosion at any time prior to the 1960's. If it is assumed that, on what would have needed to be the expert advice of a knowledgeable but reckless astrophysicist, Dr Sadler wrote the page 464 material into the Urantia Papers subsequent to the concepts on neutrinos appearing in the Gamow et al. publications, then it becomes necessary to ask why was it not removed when that work lost credibility later in the 1940's?—and particularly so since, in their conclusions, Gamow and Schoenfeld drew attention to the fact that the neutrinos were still considered to be highly hypothetical particles as well as noting that "the dynamics of the collapse represents very serious mathematical difficulties." Printing Plates for The Urantia Book Documents held by the Urantia Foundation show that the contract to prepare the nickel printing plates from the manuscript of the Urantia Papers was accepted during September, 1941. The galley proofs from the plates were checked for typographical errors by members of Dr Sadler's group, known as the Forum, in 1942. The Sherman affair described in Gardner's book included an attempt by Sherman to get control of the printing plates in 1943. These plates were held in the vaults of the printers, R.R. Donnelley & Sons until the actual printing of The Urantia Book. Wartime regulations prevented an early printing of the book. Later it was delayed by the revelators.

It has already been indicated that the highly speculative 1942 paper of Gamow and Schoenfeld was unlikely to have been the source of the book's p.464 statement on star implosion. The evidence for the printing plates contract makes it even less likely.

Invoking Occam's Razor

The language, level of knowledge, and terminology of the page 464 reference, together with the references to the binding together of protons and neutrons in the atomic nucleus, the two types of mesotron, and the involvement of small uncharged particles in beta radioactive decay as described on page 479, is that of the early 1930's period, and not that of the 40's and 50's. It is what would be expected from authors constrained by a mandate not to reveal unearned knowledge except in special circumstances. Applying the Occam's razor principle of giving preference to the simplest explanation consistent with the facts, the most probable explanation for the aforementioned material of page 464 must be that it is original to the Urantia Papers as received in 1934, hence comes into the category nominated in the revelatory mandate as information supplied to fill missing gaps in our knowledge.

References 1. Asimov, Isaac, (1966) The Neutrino (Dobson Books Ltd., London) 2. Burbidge, E.M., G.R. Burbidge, W.A. Fowler, & F. Hoyle. (1957) 3. Morrison, Philip, (1962) Scientific American 207 (2) 90. 4. Overbye, Dennis (1991) Lonely Hearts of the Cosmos (HarperCollins) 5. Thorne, K.S. (1994) Black Holes and Time Warps: Einstein's Outrageous Legacy (Picador, London)

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Majeston
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« Reply #1 on: May 07, 2007, 10:17:17 am »

Quote
= Merlin
Alright, this is new information, so let's go with it.  To begin with, the author of this article is missing some information.  Allow me to fill in the blank(s).  In 1920, Lord Rutherford postulated the existence of a neutral particle, with the approximate mass of a proton, that could result from the capture of an electron by a proton. He further postulated that it would be completely neutral and that it is the mechanism behind "natural" (as he put it) radiation.  This set of postulation stimulated a search for the particle later dubbed, Neutron. Unfortunately, the electrical neutrality itself complicated the search because all experimental techniques of the time period measured charged particles.   The period between 1920 and 1940 saw an enormous amount of work on the subject of the "un-named particle" where practically ever lab in the world was striving to be first to prove its existence.

In 1928, Walter Bothe and Herbert Becker, took an initial primary step in the search and discovery. Bombarding beryllium with alpha particles emitted from polonium, they found that it gave off a penetrating, electrically neutral radiation, (just as Rutherford predicted) which they interpreted to be high-energy gamma photons.  In 1932, Irene Joliot-Curie and Frederic Joliot-Curie used a strong polonium alpha source to further investigate Bothe’s penetrating radiation. They found that this radiation ejected protons from a paraffin target; amazing in itself because photons have no mass. Unfortunately, however, the Joliot-Curies interpreted the results as the action of photons on the hydrogen atoms in paraffin.  They, like Rutherford, Bothe and Becker before them have discovered neutrons - but they missed it.  The story does get better though - hand in there old friend.

That same week, James Chadwick reported to Lord Rutherford on the Joliot-Curies’ results.  Rutherford was astonished that they had missed the significance of their work and immediately set Chadwick on to duplicated it.   He not only bombarded the hydrogen atoms in paraffin with the beryllium emissions, but also helium, nitrogen, carbon and lithium.  By comparing the recoiling charged particles' energies from different targets, he proved that the beryllium emissions contained Rutherford's mystery particle (a neutral component with a mass approximately equal to that of the proton). He called it the neutron in a paper published in the February 17, 1932, issue of Nature.  So there we have it - almost 20 years of discussion of the mythical particle, its inclusion in science fiction for 10 of those years and finally a conclusion in 1935 with Chadwick winning the Nobel Prize for his work.  That's a storybook ending if I have ever heard one.  The beuty of the neutron is that it is relatively massive but neutral.  It is scarcely affected by the cloud of electrons surrounding the nucleus or by the positive electrical barrier of the nucleus itself; thus it penetrates the nucleus of any element and displaces photons, electrons and neutrinos as it goes..  It is the ultimate wedding crasher, but it leaves tell-tale signs as it travels.

In 1934, Walter Baade and Fritz Zwicky proposed the idea that supernova were occuring in clusters of galaxies (Baade, Walter & F. Zwicky, “On Super-Novae,” Proc. of the Nat. Acad. of Sci. 20, 254, 1934a), and they they ultimately led to the formation of Neutron stars (Baade, Walter & F. Zwicky, “Supernovae and Cosmic rays,” Physical Review 45, 138, 1934b).  Both "prophecies" were printed in 1934, but their origins were much earlier.  The two of them had been working on this explanation for years (at least 12), and it wasn't until Chadwik's discovery and subsequent naming in 1932 that they were able to conclude their search. 

On a separate (but related) note, Zwicky himself proposed the idea in that same time period, 1932-1935, that there was an enormous amount of unseen mass in the Coma Cluster when the virial theorem was applied.  This would begin the search for an explanation that would later include Dark Matter.  He also proposed the hypothesis that galaxies acted as gravitational lenses...  Between 1934 and 1950, Neutrons and neutron stars were so widely written about that it would have been impossible to not know about them.  Zwicky himself talked about them on television programs and radio shows and estimated 300 times in the 1930s alone - according to his autobiography.  His complete theorem was wholly adopted by the mainstream in 1960s, meaning that it finally hit the textbooks then, but the astrophysical society had been using it since 1937, because it made mathematical sense.  I'll grant you that it did not enjoy "mainstream" success in the 1930s, but not much of the emerging science in the first half of the 20th century did.  Even Einstein's work was 15 years prior was slow to convert the converts.

Now, if we wish to talk about Neutrinos as the "tiny neutral particles", then we have a problem.  We know that there are no suns made from neutrinos.  However, I should point out that neutrinos were not first theorized in '32 or '33.  They were theorized in 1922 and not written about by Pauli until 1930; finally published in 1931.  Mathematical proof was given in 1933-1934 accepted by the German and Italian science journals.  Enrico named it in 1934, "little neutral one" in Italian:  Neutrino.  The American/English Journals did not accept the publication until 1938 (published 1939), but they did so because the paper(s) had already been in the country in 12 different languages for the past 5 years - and then there was the Nobel Prize for his work in 1938...  Yep - the Americans and Brits blew it big time by excluding him, only to accept it after the rest of the world had, and had rewarded him with the Top Prize.   Wolfgang got his prize 7 years later.

Anyway, the fact that the neutrinos weren't actually detected until 1955 and reported in '56 isn't important; mathematically, everyone knew that they were there...  Only our technology had to catch up with our science. 

Quote from: Majeston on May 05, 2007, 06:37:54 pm
The idea of a neutron star was considered to be highly speculative right up until 1967. Most astronomers believed that stars of average size, like our sun, up to stars that are very massive, finished their lives as white dwarfs. The theoretical properties of neutron stars were just too preposterous; for example, a thimble full would weigh about 100 million tonnes. A favored alternative proposal was that large stars were presumed to blow off their surplus mass a piece at a time until they got below the Chandrasekhar limit of 1.4 solar masses, when they could retire as respectable white dwarfs. This process did not entail the release of vast quantities of tiny particles devoid of electric potential that accompany star collapse as described in the cited Urantia Book quotation.

This is and isn't the case.  Though its prediction came in the early 30s, its discovery came in the late 60s (Like the neutrino - technology lagged science).  The fact is, neutron stars gained in acceptance linearly with every new scientific proof published.  By the time of the UB's publishing, it was a well accepted object (like the neutrino).

If I get the time, I'll come back to this later.  For now, though, I would say that this paper was not researched as well as it appears.  "Publication date" is not synonymous with discovery - particularly in the early 20th century.  Those dates can lag each other by 10 or more years.  I would also say that, because of the lag in discovery and hypothesis of the two objects we are discussing, I am not surprised that the UB is very vague on the topics...  Had they waited until the 50s to publish, their science would have been a bit more correct.  All-in-all, the science of the UB remains in the 30s-40s, and inaccurate.
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