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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 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 neutron-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 Cosmos"4 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 supernovas 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 ad Schoenberg drew attention to the fact that, "the neutrinos are still considered as highly hypothetical particles because of the failure of all efforts to detect them," as well as noting that "the dynamics of the collapse represents very serious mathematical difficulties. "
Printing Plates for The Urantia Book
As a result of the Maaherra affair, documentary evidence has come to light to show that acceptance of the contract to prepare the metal printing plates from the manuscript of the Urantia Papers occurred in September, 1941. Printing technology of the time required a separate metal plate for each individual page. Hence, deletions, additions, and alterations that carried through to other pages could be enormously expensive and were avoided if at all possible.
It has already been indicated that the highly speculative 1942 paper of Gamow and Schoenberg was unlikely to have been the source of the book's p. 464 statement on star implosion. The new evidence regarding printing plates makes it even more unlikely.
Invoking Occam's Razor
The language, level of knowledge, and the terminology of the page 464 reference, together with the references to the binding together of protons and neutrons in the atomic
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