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Author Topic:   Are Uranium Halos the best evidence of (a) an old earth AND (b) constant physics?
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 139 of 142 (823477)
11-10-2017 3:34 PM
Reply to: Message 138 by RAZD
11-08-2017 11:36 AM


Cliff Notes
  1. The basic radiohalo principle is simple: radioactivity produces alpha decay, and the alpha particle have a certain energy (usually measured in million electron volts, MeV) based on the familiar e=mc² formula and the conservation of energy/mass (see ref):
    M1 = M2 + mp + e/c²
    Thus when you have an isotope decaying into another isotope by alpha decay, the energy of the alpha particle is consistent for that isotope decay and unique for that decay stage because of the unique before and after mass of the decaying isotope and the constant mass of the alpha particle.
    This consistent and unique energy then determines how far (on average) an alpha particle will travel before it gets stopped and absorbed into the surrounding material (which causes the ring pattern to be visible) and the result is a halo or a number of halos around decaying inclusions that look like rings, but are actually spherical, and something like this:
    The halos require many more than one particle to form as each particle only makes a single point on the ring. Thus uranium, with it's long half-life, takes "several hundred million years to form."
  2. From Alpha Barrier Penetration
    quote:
    The energy of emitted alpha particles was a mystery to early investigators because it was evident that they did not have enough energy, according to classical physics, to escape the nucleus. Once an approximate size of the nucleus was obtained by Rutherford scattering, one could calculate the height of the Coulomb barrier at the radius of the nucleus. It was evident that this energy was several times higher than the observed alpha particle energies. There was also an incredible range of half lives for the alpha particle which could not be explained by anything in classical physics.
    The resolution of this dilemma came with the realization that there was a finite probability that the alpha particle could penetrate the wall by quantum mechanical tunneling. Using tunneling, Gamow was able to calculate a dependence for the half-life as a function of alpha particle energy which was in agreement with experimental observations.
    This is a non-linear inverse relationship between half-life and alpha particle enegy.
  3. Alpha Tunneling Model
    quote:
    The illustration represents an attempt to model the alpha decay characteristics of polonium-212, which emits an 8.78 MeV alpha particle with a half-life of 0.3 microseconds. The Coulomb barrier faced by an alpha particle with this energy is about 26 MeV, so by classical physics it cannot escape at all. Quantum mechanical tunneling gives a small probability that the alpha can penetrate the barrier. To evaluate this probability, the alpha particle inside the nucleus is represented by a free-particle wavefunction subject to the nuclear potential. Inside the barrier, the solution to the Schrodinger equation becomes a decaying exponential. Calculating the ratio of the wavefunction outside the barrier and inside and squaring that ratio gives the probability of alpha emission.
    Change the decay rate, and you change the energy of the alpha particle. Again, it is not a linear inverse relationship, so changing physical constants to change the decay rate changes the rates for different isotopes to different degrees.
    Thus if you jigger the physics to make one ring at the proper distance but with fast decay the other rings will not be in the proper locations.
  4. (PDF) On the Effectiveness of Gamow's Method for Calculating Decay Rates
    quote:
    We examine Gamow's method for calculating the decay rate of a wave function initially located within a potential well. Using elementary techniques, we examine a very simple, exactly solvable model, in order to show why it is so reliable for calculating decay rates, in spite of its conceptual problems. We also discuss the regime of validity of the exponential decay law.
    ... (lots of formulas with undefined symbols, have fun) ...
    The decay rate is calculated from the decay energy, and these calculated values matche the empirically tested and derived values, so there you have it -- a direct link between decay energy and the half-life of the isotopes.
    Note again that this is not a linear function, so doubling the decay rate results in different decay energies of the alpha particles from all the different isotopes and they don't have the same ratios one to the next as we observe with today's decay rates. This means that any change is detectable.
  5. Note that not only do we have fully formed uranium halos, but the halos for each different element in the decay change are at the same relative location to each other based on current alpha decay energies. When you look at the decay chain for 238U you see:
    Radioactive decay - Wikipedia
    quote:
    An example is the natural decay chain of 238U which is as follows:
    • decays, through alpha-emission, with a half-life of 4.5 billion years to thorium-234
    • which decays, through beta-emission, with a half-life of 24 days to protactinium-234
    • which decays, through beta-emission, with a half-life of 1.2 minutes to uranium-234
    • which decays, through alpha-emission, with a half-life of 240 thousand years to thorium-230
    • which decays, through alpha-emission, with a half-life of 77 thousand years to radium-226 ...

    And the top three alpha decay events all have half-lives well in excess of any young earth fantasy model, so all three would need to be altered by magic in such a way that they still provide the same halo diameter ...
    Change the physics to affect one, and not only do you have the problem of this also changing the alpha particle energy (and hence the halo diameter for that isotope), so that you need an additional "correction" of the alpha energy, but you have the problem of changing the other isotope decay rates and alpha particle energies to a different degree, that must now all individually be "corrected" by further adjustments to the physics while not undoing the "corrections" already made .....
The evidence speaks for itself: the earth is old.
Enjoy

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This message is a reply to:
 Message 138 by RAZD, posted 11-08-2017 11:36 AM RAZD has replied

Replies to this message:
 Message 140 by RAZD, posted 11-10-2017 4:47 PM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 140 of 142 (823482)
11-10-2017 4:47 PM
Reply to: Message 139 by RAZD
11-10-2017 3:34 PM


Including the Oklo Natural Reactors
quote:
The Workings of an Ancient Nuclear Reactor
Two billion years ago parts of an African uranium deposit spontaneously underwent nuclear fission. The details of this remarkable phenomenon are just now becoming clear
Scientific American: By Alex P. Meshik on January 26, 2009
In May 1972 a worker at a nuclear fuel—processing plant in France noticed something suspicious. He had been conducting a routine analysis of uranium derived from a seemingly ordinary source of ore. As is the case with all natural uranium, the material under study contained three isotopes that is to say, three forms with differing atomic masses: uranium 238, the most abundant variety; uranium 234, the rarest; and uranium 235, the isotope that is coveted because it can sustain a nuclear chain reaction. Elsewhere in the earth’s crust, on the moon and even in meteorites, uranium 235 atoms make up 0.720 percent of the total. But in these samples, which came from the Oklo deposit in Gabon (a former French colony in west equatorial Africa), uranium 235 constituted just 0.717 percent. That tiny discrepancy was enough to alert French scientists that something strange had happened. Further analyses showed that ore from at least one part of the mine was far short on uranium 235: some 200 kilograms appeared to be missing ....
... In 1953 George W. Wetherill of the University of California at Los Angeles and Mark G. Inghram of the University of Chicago pointed out that some uranium deposits might have once operated as natural versions of the nuclear fission reactors that were then becoming popular. Shortly thereafter, Paul K. Kuroda, a chemist from the University of Arkansas, calculated what it would take for a uraniumore body spontaneously to undergo selfsustained fission. ...
Kuroda’s first condition was that the size of the uranium deposit should exceed the average length that fission-inducing neutrons travel, about two thirds of a meter. This requirement helps to ensure that the neutrons given off by one fissioning nucleus are absorbed by another before escaping from the uranium vein.
A second prerequisite is that uranium 235 must be present in sufficient abundance. Today even the most massive and concentrated uranium deposit cannot become a nuclear reactor, because the uranium 235 concentration, at less than 1 percent, is just too low. But this isotope is radioactive and decays about six times faster than does uranium 238, which indicates that the fissile fraction was much higher in the distant past. For example, two billion years ago (about when the Oklo deposit formed) uranium 235 must have constituted approximately 3 percent, which is roughly the level provided artificially in the enriched uranium used to fuel most nuclear power stations.
The third important ingredient is a neutron moderator, a substance that can slow the neutrons given off when a uranium nucleus splits so that they are more apt to induce other uranium nuclei to break apart. Finally, there should be no significant amounts of boron, lithium or other so-called poisons, which absorb neutrons and would thus bring any nuclear reaction to a swift halt.
Amazingly, the actual conditions that prevailed two billion years ago in what researchers eventually determined to be 16 separate areas within the Oklo and adjacent Okelobondo uranium mines were very close to what Kuroda outlined ....
Proof in the Light Elements
Physicists confirmed the basic idea that natural fission reactions were responsible for the depletion in uranium 235 at Oklo quite soon after the anomalous uranium was discovered. Indisputable proof came from an examination of the new, lighter elements created when a heavy nucleus is broken in two. The abundance of these fission products proved so high that no other conclusion could be drawn. A nuclear chain reaction very much like the one that Enrico Fermi and his colleagues famously demonstrated in 1942 had certainly taken place, all on its own and some two billion years before.
... some of the neutrons released during the fission of uranium 235 were captured by the more abundant uranium 238, which became uranium 239 and, after emitting two electrons, turned into plutonium 239. More than two tons of this plutonium isotope were generated within the Oklo deposit. Although almost all this material, which has a 24,000-year halflife, has since disappeared (primarily through natural radioactive decay), some of the plutonium itself underwent fission, as attested by the presence of its characteristic fission products. The abundance of those lighter elements allowed scientists to deduce that fission reactions must have gone on for hundreds of thousands of years ....
Nature’s Operating Schedule
After my colleagues and I had worked out in a general way how the observed set of xenon isotopes was created inside the aluminum phosphate grains, we attempted to model the process mathematically. This exercise revealed much about the timing of reactor operation, with all xenon isotopes providing pretty much the same answer. The Oklo reactor we studied had switched on for 30 minutes and off for at least 2.5 hours. The pattern is not unlike what one sees in some geysers, which slowly heat up, boil off their supply of groundwater in a spectacular display, refill, and repeat the cycle, day in and day out, year after year. This similarity supports the notion not only that groundwater passing through the Oklo deposit was a neutron moderator but also that its boiling away at times accounted for the self-regulation that protected these natural reactors from destruction. In this regard, it was extremely effective, allowing not a single meltdown or explosion during hundreds of thousands of years. ...
So one of the results was that the decay process produced not just alpha and beta decay particles and the isotopes made by their removal by decay, but also the rarer fission into two much larger products: the "new, lighter elements" and their abundance confirmed that a nuclear chain reaction similar to what is seen in man-made reactors. We also see that the "plutonium itself underwent fission, as attested by the presence of its characteristic fission products."
What happens with a decay chain is that isotope after isotope is produced until a much smaller stable element is created by the removal of the decay particles.
But there is also an aspect of this decay process called ...
quote:
secular equilibrium
Secular equilibrium can only occur in a radioactive decay chain if the half-life of the daughter radionuclide B is much shorter than the half-life of the parent radionuclide A. In such a situation, the decay rate of A, and hence the production rate of B, is approximately constant, because the half-life of A is very long compared to the timescales being considered. The quantity of radionuclide B builds up until the number of B atoms decaying per unit time becomes equal to the number being produced per unit time; the quantity of radionuclide B then reaches a constant, equilibrium value. Assuming the initial concentration of radionuclide B is zero, full equilibrium usually takes several half-lives of radionuclide B to establish.
The quantity of radionuclide B when secular equilibrium is reached is determined by the quantity of its parent A and the half-lives of the two radionuclide. ...
Radionuclide B also produces a radionuclide C that can be in secular equilibrium , and on down to the final stable isotope.
This means that the proportions of the different decay products in a decay chain that has existed long enough to reach secular equilibrium at all levels would have specific proportions that depend on the individual isotope half-lives.
Changing the half-life of one isotope creates different changes to the other isotopes (see Message 139 above) and thus the secular equilibrium would result in a different set of proportions of the decay chain isotopes.
This was not observed at the Oklo Natural Reactors even though massive investigation and testing and evaluations were done. What they found was the same as observed in man-made reactors.
Remember that the Oklo Natural Reactors were found because the secular equilibrium level for 235U was only 99.6% of the natural decay uranium secular equilibrium levels (0.717% instead of 0.720%).
Logical Conclusion: the decay rates have not changed for over 2 billion years.
Enjoy
Edited by RAZD, : .

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This message is a reply to:
 Message 139 by RAZD, posted 11-10-2017 3:34 PM RAZD has seen this message but not replied

  
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 142 of 142 (826502)
01-03-2018 7:43 AM
Reply to: Message 141 by AlexCaledin
01-02-2018 5:51 PM


It's completely pointless to assert what actually happened two billion years ago. Things only seem that way, allowing to suggest a good model for putting some measured (and not actually interesting) things in some order - but no more than that.
So you prefer to believe in a lying god/s that create hoaxes and false narratives.
Something that I consider totally pointless, so totally pointless that you run away from any point on which to base your view of reality. What you believe in becomes a world of illusion and make believe, where anything - repeat ANYTHING - is of equal importance: none.
You have no test for reality.
Enjoy

we are limited in our ability to understand
by our ability to understand
RebelAmerican☆Zen☯Deist
... to learn ... to think ... to live ... to laugh ...
to share.


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This message is a reply to:
 Message 141 by AlexCaledin, posted 01-02-2018 5:51 PM AlexCaledin has not replied

  
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