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Spring Has Finally Arrived
80 degrees at 10:00 p.m. Finally.
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Homes
I've probably lived in thirty different places over the years, moving every one to three years in the USAF, plus the years in undergraduate and then graduate school.
I can unequivocally say that the apartment we are currently in is perhaps the "best" place I have ever lived. I love it.
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Entertainment Tonight
The DVD Woodstock: Three Days of Peace & Music. I can compare it to Monterey Pop Festival. The former, 1969; the latter, 1968.
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Cosmos Sapiens
As mentioned earlier, I continue to enjoy John Hands Cosmos Sapiens, c. 2015, first published, 2016.
John Hands is clearly in the same camp as the authors of The Privileged Planet though I doubt he would want to admit that. The authors of The Privileged Planet and John Hands all seem to agree that from the time of the Big Bang (if that did indeed occur) to the rise of humans, an infinite number of things had to have happened "just right."
John Hands said he was born and raised a Catholic; he became an atheist and now says he's agnostic. The more one reads of his book, the more difficult it is to accept that he is "simply" an agnostic. One gets the feeling he is an unwilling agnostic. Sort of like the folks who will end up voting for Hillary.
Starting on page 132, at the bottom of the page, John Hands delves into several "coincidences" that had to occur for life to begin.
One element deemed essential to humans and all known forms of life is carbon, more specifically the stable isotope carbon-12. But as Hoyle pointed out, three parameters must be highly tuned for sufficient carbon-12 to be produced in stars.The author then provides the two nuclear-chemical equations that were required. The first was the fusion of two helium molecules to form beryllium. The second was a molecule of beryllium and a molecule of helium fusing to form carbon-12.
For these reactions to proceed three conditions must be fulfilled:
- The lifetime of Be-8 (about 10^17 seconds) must be sufficiently long compared with the He-4 + He-4 collision time (about 10^21 seconds) to allow the first reaction to occur, but it must not be so stable that the chain of reactions stops here; it is.
- Fred Hoyle predicted that the yield of carbon would be negligible unless the reactions were resonant, with the vital resonance level of the carbon-12 nuclear lying near 7.7 MeV. A resonance in nuclear fusion is an energy peak at which the reaction is maximally efficient. Experimenters later confirmed that the resonance level of carbon-12 nucleus is 7.6549 MeV. This lies just above the 7.3667 MeV energy needed to fuse helium-4 and beryllium-8 and so enables this reaction to proceed.
- The fusion of carbon-12 with another helium-4 nucleus would produce an oxygen nucleus. However, oxygen-16 nucleus has an energy level at 7.1187 MeV. This lies just below the total energy of carbon-12 + helium-4 at 7.1616 MeV. If it had been higher, then nearly all of the carbon would have been rapidly removed from stellar interiors by conversion into oxygen.
Though necessary, even the conservation principles and quantum theory are not sufficient to explain how the complex organic molecules, of which we and known forms of life consist, evolved. If the values of three nuclear parameters (as noted above) were slightly different, insufficient carbon would have been generated in stars to produce organic molecules; if the values of two dimensionless constants -- the fine-structure constant and the proton-to-electron mass ratio -- were slightly different, no atoms or molecules at all would have been formed. No theory explains why these parameters have the values they do.Others have noted the same thing.
One gets the feeling that John Hands is having trouble "believing" that all this "just happened" to work out.
Just saying.
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