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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
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Message 78 of 142 (546456)
02-10-2010 11:33 PM


Summary of the decay rate problem for YECs
This came up on another thread, so I thought I'd post this here as a summary of the problem faced by YEC's that want to claim that the decay rates were different at some time in the past. The uranium halos link together several aspects that would all need to change in sync to replicate normal decay in some rapid decay scenario:
quote:
Message 1: Where I am starting is from Dr Wiens:
Radiometric Dating
quote:
At any rate, halos from uranium inclusions are far more common. Because of uranium's long half-lives, these halos take at least several hundred million years to form. Because of this, most people agree that halos provide compelling evidence for a very old Earth.
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 isotopes decaying into other isotopes by alpha decay, the energy of the alpha particle is unique to that decay stage because of the unique before and after mass of the decaying isotope and the constant mass of the alpha particle.
This unique energy then determines how far (on average) an alpha particle will travel before it gets stopped and absorbed into the surrounding material ...
... I found this interesting tid-bit in Alpha Decay, Alpha detectors and identification:
quote:
However, if the alpha has enough energy to surmount this barrier then it will regain that energy as electrostatic repulsion once it gets outside the range of the attractive strong nuclear force. One important consequence of this is that all alpha emissions have at least ~5 MeV energy. Furthermore, half-life is inversely related to decay energy.
(bold for empHASis)
Very simply put, if you change the decay rate, you change the decay energy, and the diameter of the halo changes.
There should be no characteristic uranium halos with the unique energy of uranium alpha decay from fast decay.
It appears that the relationship between decay rate and decay energy is not inversely linear, but inversely exponential (thus the isotopes with the shortest half-life produce alpha-particles with the highest energy), and it appears that the relationship between decay energy and penetration distance is not linear but polynomial (it appears that the penetration depth increases with the square of the energy).
Decreasing the half-lives by only 1/2 of the current amounts would blow the halos out of proportion to each other, increase their overall size, and only accomplish a very small minute fraction of the reduction necessary to make a young earth possible (the half-life of 238U is 4,468,000,000 years and half of that is only 2.2 billion years) --- there would be no 238 halo patterns of the proper size and proportion left from any period of vastly decreased decay rates.
FURTHERMORE, the longer half-life rings (like 238U) would not have enough time to form after the half-lives have stabilized at today's rates --- there would be no 238U rings formed in only 10,000 years.
quote:
(from Gentry's website Evidence for Earth's Instant Creation - Polonium Halos in Granite and Coal - Earth Science Associates)

None of those pictures would be possible with any significant change in the decay rate in the last hundred million years, as "these halos take at least several hundred million years to form" -- after the decay rates are stabilized at today's rates.
Enjoy.

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


Message 79 of 142 (546475)
02-11-2010 7:29 AM
Reply to: Message 10 by Coragyps
08-17-2008 2:44 PM


209Bi is radioactive but no halos are known
Hi Coragyps, going through the old replies here,
Which is how bismuth 209 can have a 3 MeV alpha decay - its half life is 10^19 years.
And there are no halos for 209Bi, because the earth hasn't existed long enough for those decay events to cause enough damage to be visible.
This is the other end of the radiometric question for why there are no examples of radioactive isotopes with short half-lives that aren't replenished by formation of new isotopes (the way 14C is formed or the way isotopes of a decay chain are formed).
Ones sets an upper limit for the age of the earth, the other sets a lower limit for the age of the earth. 4.55 billion years is in between, 10,000 years is not.
Enjoy.

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This message is a reply to:
 Message 10 by Coragyps, posted 08-17-2008 2:44 PM Coragyps has not replied

Replies to this message:
 Message 80 by lyx2no, posted 02-11-2010 4:08 PM RAZD has replied

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


Message 81 of 142 (546589)
02-11-2010 8:08 PM
Reply to: Message 80 by lyx2no
02-11-2010 4:08 PM


Re: 209Bi is radioactive but no halos are known
Hi lyx2no2
We know from Wiens that uranium takes several hundred million years to form a halo,
Radiometric Dating
quote:
At any rate, halos from uranium inclusions are far more common. Because of uranium's long half-lives, these halos take at least several hundred million years to form. Because of this, most people agree that halos provide compelling evidence for a very old Earth.
so we can ball-park it by the ratio of half-lives. From Coragyps we have
Which is how bismuth 209 can have a 3 MeV alpha decay - its half life is 10^19 years.
The half-life of 238U is 4.468x10^9 years so the ratio is
10x10^18
4.468x10^9
and we get 2.24 billion x "several hundred million years." Call it 2.24x10^9 x 1x10^8 for a barely visible halo and you get a minimum of 2.24x10^17 years, rather more that the age of the universe eh?
This is older that the dates from astronomy for the formation of the solar system, which is another outer bound measurement, but it is no wonder that there are no 209Bi halos.
Enjoy.

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


(1)
Message 82 of 142 (551723)
03-23-2010 10:58 PM


More evidence that radioactive rates have not changed
From What exactly is ID? Message 1227:
CF210: Constancy of Radioactive Decay Rates
quote:
# The half-lives of radioisotopes can be predicted from first principles through quantum mechanics. Any variation would have to come from changes to fundamental constants. According to the calculations that accurately predict half-lives, any change in fundamental constants would affect decay rates of different elements disproportionally, even when the elements decay by the same mechanism (Greenlees 2000; Krane 1987).
Which means that the radii of the different halos for the different daughter isotopes would change by different amounts - yet this is not observed in the Uranium halos .... and therefore Uranium halos are indeed evidence that the earth is very old.
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 ...
Here is the image of the theoretical 238U halo again:
And here is an image of an actual 238U halo (from Gentry):
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.
Edited by Zen Deist, : clrty

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Replies to this message:
 Message 83 by Smooth Operator, posted 03-28-2010 5:31 AM RAZD has replied

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


Message 90 of 142 (552414)
03-28-2010 10:30 PM
Reply to: Message 83 by Smooth Operator
03-28-2010 5:31 AM


Re: More evidence that radioactive rates have not changed
For the general readers, seeing as Smooth Operator will not be allowed to participate on this thread (and mess it up with the massive denial his particular world view requires), there is massive evidence of radioactive decay rates being both fixed and known to a fair degree of certainty.
Uranium halos are not evidence for an old Earth because they are based on two assumptions you don't know anything about. So let's take it step by step...
1.) Half life of U238.
1.) The claim that U238 half-life is 4.5 billion years. How do you know that? Where has this been shown to be true? You don't know that. You assume that. And since you don't know it, you don't know that it took 4.5 billion years to make ANY U238 halo.
This denial of reality is based on both a logical fallacy (argument from incredulity) and general logically false thinking. The astute reader will note that Smooth Operator did not provide any evidence of a different decay rate, he just employed the PRATT that because event X was not observed we can know nothing about event X.
Curiously, the claim that Uranium Halos are evidence of extreme age for the earth comes from a scientist who does in fact know a whole heck of a lot more about the physics involved than Smooth Operator has demonstrated (he can't even get the facts right):
Radiometric Dating
quote:
At any rate, halos from uranium inclusions are far more common. Because of uranium's long half-lives, these halos take at least several hundred million years to form. Because of this, most people agree that halos provide compelling evidence for a very old Earth.
Not just the 238U half-life, but the half-life of several of the decay products as well.
Amusingly, one does not need to observe a radioactive material for the full length of the half-life in order to measure the decay rate, as the physics involved follows very predictable paths.
If Smooth Operator's claim were true we would not know the half-life of a single element with a half-life over 50 years, while curiously, the half-lives of almost all elements are known to a high degree of precision.
Not only do we have the initial information of decay curves to provide the slopes at the beginning of exponential curves actively defining the half-life for the elements, we have parent-daughter relationships that show that the proportions of elements found does in fact correlate with the measured half-lives.
Radioactive dating methods also correlate and confirm each other, even though they are derived from materials with different half-lives and therefore different proportions of the various elements at different ages.
One example of such correlations is found with the Oklo evidence.
http://oklo.curtin.edu.au/
Another example of this is the correlation of radiocarbon dating with both annual tree rings and with organic specimens from the varves in Lake Suigetsu, showing that 14C dating methods do in fact represent the age of the specimens, because we know their age by other means, means that are more accurate than 14C (due to atmospheric variations in 14C) and which can be used to correct for the atmospheric fluctuations in the past.
However, to more fully discuss radioactive decay and dating systems that are based on this concept we would prefer a system not subject to this kind of variation seen with 14C. We also need one that can be correlated over substantial time to validate the system.
Such an example is found in
USGS URL Resolution Error Page (8)
quote:
In 1997, the Devils Hole Thorium-230 dates were independently confirmed by non-USGS investigators using Protactinium-231.
(See Broecker, 1992; Ludwig, et al., 1992; Winograd, et al., 1997; and Edwards, et al., 1997.)
Corroborated by two independent radiometric methods. The oldest date in the data table is 567,700 years ago.
So what exactly do we have here? Water dripping down a cave wall, depositing calcite and various other minerals and impurities, elements that are soluble in water, including trace levels of radioactive isotopes of uranium. Material that gets deposited with the calcite formation as the water evaporates, forming layer after layer of similar deposits, each one trapping the material in their respective layers. The calcite forms a matrix that holds the impurities, minerals and trace elements in a position related to the time the calcite was deposited.
The calcite is deposited year by year, with the soluble elements being trapped as the water evaporates, and thus dating the layers radioactively by the measurement of the relative amounts of non-soluble elements that are derived by radioactive decay of soluble radioactive elements.
In this case two independent radioactive elements, Thorium and Protactinium.
Radiometric Dating (9)
quote:
Two of the most frequently-used of these "uranium-series" systems are uranium-234 and thorium-230.
... The chemistry of uranium and thorium are such that they are in fact easily removed from each other. Uranium tends to stay dissolved in water, but thorium is insoluble in water. So a number of applications of the thorium-230 method are based on this chemical partition between uranium and thorium. ...
Comparison of uranium-234 ages with ages obtained by counting annual growth bands of corals proves that the technique is highly accurate when properly used (Edwards et al., Earth Planet. Sci. Lett. 90, 371, 1988). The method has also been used to date stalactites and stalagmites from caves, already mentioned in connection with long-term calibration of the radiocarbon method. In fact, tens of thousands of uranium-series dates have been performed on cave formations around the world.
http://www.ead.anl.gov/pub/doc/protactinium.pdf (5)
quote:
Protactinium-231 is a decay product of uranium-235 and is present at sites that processed uranium ores and associated wastes. This isotope decays by emitting an alpha particle with a half-life of 33,000 years to actinium-227, which has a half-life of 22 years and decays by emitting an alpha or beta particle.
The U-235 to Pa-231 decay is from a different series than the U-234 to Th-230 decay, so the two are independent of each other. Again, as the Devil's Hole calcite was deposited after being dissolved in water, the Pa-231 in the calcite could only come from the decay of the parent U-235, giving an accurate measurement of the age of the layers of calcite.
Exponential decay - Wikipedia (4)
quote:
A more intuitive characteristic of exponential decay for many people is the time required for the decaying quantity to fall to one half of its initial value. This time is called the half-life, and often denoted by the symbol t1/2. The half-life can be written in terms of the decay constant, or the mean lifetime, as:
t1/2 = ln2/λ = Tln2

When this expression is inserted for T in the exponential equation above, and ln2 is absorbed into the base, this equation becomes:
N(t) = N02-t/t1/2

Using the half-lives of thorium-230 (75,380 years) and protactinium-231 (32,760 years), we can now draw the exponential curves for these isotopes (with % on the y-axis and time in k-yrs on the x axis, thorium in blue and protactinium in red):
This means we have a series of data with three different pieces of information: calcite layer age by relative depth in the formation, and Thorium-230 content and Protactinium-231 content in each layer. We also note that Thorium-230 has a half-life of 75,380 years, while Protactinium-231 has a half-life of 32,760 years - less than half the half-life of Thorium-230. This means that layer by layer the ratio of Thorium-230 to Protactinium-231 is different:
   Age   THr=THf/THo PAr=PAf/PAo  THr/PAr
------------------------------------------
75,380 0.5000 0.2029 2.46
150,760 0.2500 0.0412 6.07
226,140 0.1250 0.0084 14.96
301,520 0.0625 0.0017 36.86
376,900 0.0313 0.0003 90.82
452,280 0.0156 0.0001 223.77
527,660 0.0078 0.00001 551.35
So for these dates to be invalid there would have to be a mechanism that can layer by layer preferentially change the ratio of these two {elements\isotopes} within the solid calcite vein.
Rather than just wave his hands in denial, Smooth Operator -- or anyone else trying to deny this evidence -- would have to show some reasonable method to achieve these different ratios by some other system.
This validates radioactive decay rates for the 567,000 year duration of this evidence, and confirms the half-lives for each of these isotopes.
In other words, we can have a high degree of confidence in the measured decay rates of the various elements involved from the multiple sources of information and from the correlations of information that validate these rates.
2.) Halo itself.
2.) And the second assumption, which is even worse. Is the assumption that the U238 halo was produced by a constand decay rate. And then you turn and say that since it was constant decy, it had constant energy, thus a specific halo was formed that can only be produced by constant energy. That's circular logic. Since you don't know by what energy strength was that halo formed, you don't know if it was formed by constant decay, and of course constant energy. And you don't know that, because you never saw a U238 halo form, and what energy it took to form the said halo, that you never saw form in the first place.
Again, Smooth Operator is missing the vital element of this issue: the alpha decay energy needs to be constant for the halos to form, as the diameter of the halo for each different isotope in the decay series is fixed by the unique alpha decay energy for that isotope.
Nobody needs to observe the halo being formed to see that the result is due to the alpha decay energies being the same for each isotope in the series over a period of time long enough for all the alpha decay events to have occurred.
Due to the physics involved, decay energy, whether alpha or beta, is related to the half-life of the particular isotope. Each isotope that decays by alpha decay has a unique alpha decay energy specific to that kind of decay event. This physics also shows that if you change the decay rate that this results in change to the alpha energy.
Further the physics shows that any change to the basics of decay will affect different isotopes to different degrees, so the change to one isotope's alpha decay rate\energy will be different from the change to another isotope's alpha decay rate\energy.
Thus the problem that needs to be explained is how all these decay events actually occurred with the precise alpha energy to form the halos if the decay rates were different. Each isotope decay rate change needs to be "juggled" in a different degree to explain the evidence of the halos.
Saying that there is evidence of decay rate changes (even if true) and saying that there is evidence of alpha energy changes (also even if true) does not show how this is coordinated to produce the halo at the correct diameter.
One needs to complete an alternate explanation that fully explains all the evidence, not just denial of the explanation provided by physics, the halos, and an old age for the earth.
Smooth Operator has not done this. His premises are false, and therefore all his conclusions are invalid.
I have no interest in debating Smooth Operator further on this issue, until he can show how each precise alpha decay energy can be produce by some other method, and demonstrate that decay rates can be changed by factors of thousands while producing the same alpha decay energy. He can start another thread to do this.
Enjoy.
Edited by RAZD, : added wiens
Edited by RAZD, : table alignments
Edited by RAZD, : .

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This message is a reply to:
 Message 83 by Smooth Operator, posted 03-28-2010 5:31 AM Smooth Operator has not replied

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


Message 91 of 142 (647163)
01-08-2012 9:15 AM


Moved from Message 61 on the How did the Aborigines get to Australia? thread
Hi foreveryoung,
If the decay energy is the energy releassed by a "single" radioactive decay, why would the timing of those decays have any effect of the energy of any one decay?
From link previously provided (Are Uranium Halos the best evidence of (a) an old earth AND (b) constant physics?):
quote:
Not being a physicist, I am not familiar with the equations that link decay rate to decay energy, so I am going on memory, but I found this interesting tid-bit in Alpha Decay, Alpha detectors and identification:
quote:
However, if the alpha has enough energy to surmount this barrier then it will regain that energy as electrostatic repulsion once it gets outside the range of the attractive strong nuclear force. One important consequence of this is that all alpha emissions have at least ~5 MeV energy. Furthermore, half-life is inversely related to decay energy.
(bold for empHASis)
If you look at Message 7 of that thread you will see this:
quote:
From Alpha Barrier Penetration
... 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.
Thus you can see the experimental data that shows the inverse relationship discussed, and reference is made to the calculations relating alpha particle energy (inversely) to half-life (ie decay rate). Note that the vertical scale is a log scale, so the relationship is not a linear inverse relationship but a logarithmic inverse one.
Message 8 gives us this information:
quote:
Alpha Tunneling Model
... 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.
If you increase the rate of decay then the barrier is easier to penetrate and the particles will have more energy outside the barrier. Change in the energy outside would show up in the halos.
Due to the extreme age necessary to form a uranium halo, we can be sure that the decay energy has not changed significantly during their formation, and thus that the decay rate has not changed in "at least several hundred million years" (to quote Dr Wiens on his Radiometric Dating, A Christian Perspective website.
Enjoy.
Edited by Zen Deist, : moved
Edited by Zen Deist, : clrty

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Replies to this message:
 Message 92 by foreveryoung, posted 01-08-2012 10:08 AM RAZD has replied

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


Message 93 of 142 (647264)
01-08-2012 10:00 PM
Reply to: Message 92 by foreveryoung
01-08-2012 10:08 AM


Hi foreveryoung,
Yes, there is an inverse relation there that I see. ...
The closest I've found to having the formulas (so far) was on Message 9, unfortunately the link is broken (these are notes for a physics class, and subject to change every year. The quote on that post is from 2007 year courses. There were several pages of formulas, but they did derive the decay constant from the alpha particle energy.
... The question is: does the inverse relation go both ways? ...
Yes.
One of the laws of physics is that reactions are reversible.
... If a higher decay energy translates into a shorter half life, that is fine. ...
And the evidence of the Uranium halos shows that this did not occur.
... If a shorter half life translates into a higher decay energy, then my theory goes down the tubes. Can you show the later?
Decay rate is a function of alpha particle energy: faster decay rate = shorter half-life = higher decay energy.
Alpha particle energy is a function of the decay rate: higher decay energy = shorter half-life = faster decay rate.
These are saying the same thing.
Enjoy.

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This message is a reply to:
 Message 92 by foreveryoung, posted 01-08-2012 10:08 AM foreveryoung has replied

Replies to this message:
 Message 96 by foreveryoung, posted 01-09-2012 11:02 PM RAZD has replied

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


Message 98 of 142 (647529)
01-10-2012 7:55 AM
Reply to: Message 97 by NoNukes
01-09-2012 11:33 PM


new topic needed
Hi NoNukes and foreverryoung,
If the speed of light was higher in the past than it is today, isn't it possible that the decay rate of all unstable isotopes would be lower?
Fast light cures all eh?
I'm game to entertain the idea that you are not grasping at straws. Why don't you describe a mechanism for lowered light speeds to affect alpha particle decay rates, such that the mechanism does so without affecting decay energy, some evidence that such a mechanism ever existed, and some evidence that the speed of light has changed in the last few hundred million years. Then perhaps we'll discuss supernova 1987a.
And by the way, your proposed mechanism should affect decay rates in such a way that dating methods which overlap in date range give comparable results.
You don't have to do all the work yourself. You can cite someone else's work. I'd be happy to rip into it.
Sounds like a great new topic.
Curiously supernova 1987a also provides information on decay rates long ago ...
Enjoy.

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This message is a reply to:
 Message 97 by NoNukes, posted 01-09-2012 11:33 PM NoNukes has seen this message but not replied

  
RAZD
Member (Idle past 1404 days)
Posts: 20714
From: the other end of the sidewalk
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Message 99 of 142 (647555)
01-10-2012 9:53 AM
Reply to: Message 96 by foreveryoung
01-09-2012 11:02 PM


Hi foreveryoung,
... I say that there could be other mechanisms beside increasing decay energies that could cause faster decay rates. I think a faster speed of light would do the job. ...
quote:
from Message 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 isotopes decaying into other isotopes by alpha decay, the energy of the alpha particle is unique to that decay stage because of the unique before and after mass of the decaying isotope and the constant mass of the alpha particle.
M1 is the atomic mass before decay, M2 is the atomic mass after the decay, mp is the mass of the decay particle, e is the energy of the decay particle and c is the constant called the speed of light
Speed of light - Wikipedia
quote:
The speed of light in vacuum, usually denoted by c, is a physical constant important in many areas of physics. Its value is 299,792,458 metres per second, a figure that is exact since the length of the metre is defined from this constant and the international standard for time.[1] In imperial units this speed is approximately 186,282 miles per second.
Tell you what: start a new thread on this concept, and then if you can show that this would actually work and provide evidence that it could have happened, then you can bring that result back here.
The laws of physics may determine that reactions are reversible, but we are not talking about reversing a reaction. An unstable isotope decays and the decay occurs at a particular decay energy. It has been shown that the faster the decay occurs, the greater the decay energy of each decay. We are not asking the reverse that decay so the point is moot.
Thus faster decay would cause greater decay energy, and this would show up in the uranium halos. Again we see where there is a known relationship between decay rate and decay energy (even if we don't have the actual formulas to show it, see Message 7):
quote:
... 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.
We know that a relationship exists, we (here on this forum) don't know what it is. If we had Gamow's calculations we would have that information.
... You say that shorter half lives creating faster decay rates is the same thing as saying higher decay energies creating faster decay rates. ...
Correct. Perhaps you are confusing yourself between decay rate and half-life. Decay rate and half-life are two different ways for expressing the same thing:
Half-life - Wikipedia
quote:
  • t1/2 is the half-life of the decaying quantity,
  • τ is a positive number called the mean lifetime of the decaying quantity,
  • λ is a positive number called the decay constant of the decaying quantity.
The three parameters t1/2, τ, and λ are all directly related in the following way:
t1/2 = ln(2)/λ = τ•ln(2)
where ln(2) is the natural logarithm of 2 (approximately 0.693).
Thus the decay rate, λ, = ln(2)/t1/2, the half-life.
Thus the relationship between the decay rate, λ, and decay energy, e, is also the relationship between ln(2)/t1/2 and decay energy (or t1/2 and ln(2)/e).
We can get the values for decay rate and decay energy and plot them if you want to.
You said that uranium halo evidence shows that higher decay energies did not occur. Your logic is that since the halos are the same size throughout all geological history, and since decay energy is related to halo size, and since decay energy is inversely related to decay rate, the decay rate must have always been the same. ...
Correct except that decay energy is inversely related to half-life, half-life is inversely related to decay rate (see above).
... Alpha particle energy is a function of the decay rate? You cannot establish this. ...
I believe it is shown. We would have more detail if we had Gamow's calculations, but we know that it has been calculated.
Unless you know all the possible mechanisms for determine the rate of decay, your function cannot be established.
This seems to be related:
Gamow factor - Wikipedia
quote:
The Gamow Factor or Gamow-Sommerfeld Factor[1], named after its discoverer George Gamow, is a probability factor for two nuclear particles' chance of overcoming the Coulomb barrier in order to undergo nuclear reactions, for example in nuclear fusion. By classical physics, there is almost no possibility for protons to fuse by crossing each other's Coulomb barrier, but when George Gamow instead applied quantum mechanics to the problem, he found that there was a significant chance for the fusion due to tunneling.
This probability increases rapidly with increasing particle energy, but at a given temperature the probability of a particle having a high energy falls off rapidly, following the Maxwell-Boltzmann distribution. Gamow found that, taken together, these effects mean that for any given temperature, the particles that actually fuse are mostly in a (temperature-dependent) narrow range of energies known as the Gamow window.[2]
Oh look, I found this by googling gamow decay energy calculation
http://www.phy.uct.ac.za/courses/phy300w/np/ch1/node38.html
quote:
... (several formulas with undefined symbols, have fun) ...
The Geiger-Nutall equation is thus recovered. Note the extreme sensitivity of the decay constant on the energy in the above equation.
Change the decay rate and you change the energy of the decay particle.
and
(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.
Enjoy.
Edited by Zen Deist, : c what I mean
Edited by Zen Deist, : took circle out of message link
Edited by Zen Deist, : code/space

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RAZD
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Posts: 20714
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Message 101 of 142 (647603)
01-10-2012 1:02 PM
Reply to: Message 100 by NoNukes
01-10-2012 12:01 PM


possibilities?
Hi NoNukes,
To be fair to foreveryoung, he seems to be proposing that some property that we are taking as constant might have changed with the result that the known relationship between decay energy and decay rate would also change.
Of course the obvious question to ask before pursuing such a possibility is why would the decay energy remain constant under a change in the relationship? After all, that is the value that affects the halos. In other words, if some property of the universe is not constant as we assume, then why is decay energy fundamental and constant?
Yes, this is the kind of double bind that the Age Correlations and An Old Earth, Version 2 No 1 thread creates - not only do they have to explain some mechanism to alter each different method for measuring time but also why they correlate.
So yeah, I'm skeptical that foreveryoung might be right. But...
Maybe the answer would pop out of the analysis of Gamow's equations. If so then foreveryoung's question would seem to be on topic. He's fixed on the speed of light, but even the speed of light is based on other constants (permeability and permittivity of free space) that define some kind of "stiffness" of the space-time. And we might come up with other possibilities like charge or mass of some fundamental particle(s).
I've gotta get to doing some real work, but I'm going to take a look at those links of yours real soon.
A possibility of course. I have trouble with the equations in the links because they don't define what the symbols mean, so it is hard to understand what they are talking about where they talk about it.
Enjoy

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RAZD
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Message 102 of 142 (647607)
01-10-2012 1:23 PM


Terminology Error Report
For all readers,
I find that I have committed an error in terminology by confusing decay rate with the decay constant, λ, where the decay rate involves the total decay from a radioactive mass within a set period of time:
http://hyperphysics.phy-astr.gsu.edu/...nuclear/halfli2.html
quote:
Radioactive decay is a statistical process which depends upon the instability of the particular radioisotope, but which for any given nucleus in a sample is completely unpredictable. The decay process and the observed half-life dependence of radioactivity can be predicted by assuming that individual nuclear decays are purely random events. If there are N radioactive nuclei at some time t, then the number ΔN which would decay in any given time interval Δt would be proportional to N:
ΔN = -λ•N•Δt
where λ is a constant of proportionality (decay constant).
Without any further assumptions, this leads to the exponential radioactive decay result:
N = N0•e-λ•t
and also implies that the decay rate and amount of emitted radiation also follow the same type of relationship:
R = R0•e-λ•t

Where R is the decay rate and λ is the decay constant.
Hopefully it will not create terminal confusion if I say that in previous posts where I have said decay rate I should have said decay constant, except where it is taken from a quote from an article that uses the term decay rate.
Thus we can say that the decay rate was higher in the past because there was more material decaying, just as the decay rate in radioactive lumps today are lower than they were yesterday or last year.
This is accounted for in the radioactive dating methods, so to change the dating method results what creationists really want is a higher decay constant (shorter half-life).
Decay Rate: the amount of decay events from a mass of radioactive material within a set time period, dependent on the quantity of radioactive material and the decay constant.
Decay Constant: the ratio of the number of radioactive atoms disintegrating in any specified short unit interval of time to the total number of those atoms.
mea culpa
Enjoy.
Edited by Zen Deist, : clrty

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Message 104 of 142 (667682)
07-11-2012 7:39 AM


bump for foreveryoung
Hi again foreveryoung, thought you might want to bring your question here:
Proposed New Topics radiohaloes and differing masses Message 1:
If the sub atomic particles of a uranium or radon atom were of less mass in the distant past, why would their respective radiohaloes be of a different size?
I did some reading about this during my suspension and was ready to reengage with I returned only to find it is in summation mode. Jar has already avoided the first thread that I spun off from the original one. Perhaps someone else is willing to take up where he left off.
It has to do with the conservation of momentum and energy among other things.
In Message 99 I repeated the equation from Message 1:
quote:
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 isotopes decaying into other isotopes by alpha decay, the energy of the alpha particle is unique to that decay stage because of the unique before and after mass of the decaying isotope and the constant mass of the alpha particle.
If you change masses by some proportion, then e has to change as well.
Enjoy.

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Message 129 of 142 (667772)
07-12-2012 6:15 AM
Reply to: Message 106 by foreveryoung
07-11-2012 12:32 PM


Re: bump for foreveryoung
Hi foreveryoung,
If the speed of light were the same as today, you would have a point. A changing speed of light was the main issue in the thread I started months ago. Many other constants and particularly rest mass would be affected as well. Jar insisted through the Oklo reactor example and the resulting radiohaloes that a changing mass would show up in the haloes. That is what brings us here today.
I am aware of this, having also been in that other discussion.
The problem is that you change one thing, that results in a number of other changes that must also be made, and each of those changes result in more things that need to be changed, and you end up with a world of illusions.
* I also don't think that this helps you. If you change the mass of the elements to 1/100th this only increases the speed of light by a factor of 10 to keep the energy of the alpha particle the same.
Then we look at this effect on gravity, simplistically with Newton's law first:
G = gmM/d2
Both m and M are now 1/100th of current values so the force of gravity is reduced to 1/10,000 of today's values, and this affects orbits etc etc etc *
I am not sure what "mp" means in the conservation of energy equation you posted. I am sure it must be the mass of the alpha particle. The energy that propels the alpha particle and the daughter isotope away at tremendous speed comes from the missing mass that is realized when you compare the mass of the parent isotope to that of the daughter isotope and the alpha particle.
Correct, for alpha decay. In beta decay it would be the mass of the beta particle (electron), and in gamma decay it would be the mass of the gamma particle.
Of course we are only interested in alpha particles for ring formations.
Just from the equation you gave me, a smaller mass for the parent and daughter products would not show up in a smaller kinetic energy if the speed of light were greater.
And of course to be just exactly the right amount of change so that the energy is mysteriously maintained while everything else in the equation changes.
Apart from that, I would like to know what atomic mechanism is responsible for the missing mass that shows up as kinetic energy in driving away the daughter products?
You'll have to ask one of the physics mavens that one.
Enjoy.
Edited by RAZD, : * to * added by edit

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Message 130 of 142 (667774)
07-12-2012 6:39 AM
Reply to: Message 113 by foreveryoung
07-11-2012 4:55 PM


theory vs hypothesis vs concept
Hi again foreveryoung
Message 110: What is driving the changing speed of light, rest mass, gravitational force, etc.. is a changing zero point energy field. If that field were void of energy, IOW, no field present at all, all atoms would have zero mass and light would travel at infinite speed. Gravity is the simply the drag that field puts on an accelerating particle. Regions of space that exert more gravity than others have more particles in them. This isn't because of some imaginary "mass" we assign to particles. It is because when a particle is jiggled around by that field, it sends out a field all its own. When you combine several of those particle fields together, you have what is seen as the gravitational force.
And atoms would not exist ... in a zero energy field there would be no force to hold the atomic particles together.
To see what a zero energy field would be like consider the end of the universe when thermodynamics has reduced everything to the point that no energy is left. Would the speed of light be infinite then?
This all sounds like you guys have your ears plugged and refuse to entertain the notion at all.
Perhaps because that's all it is? If you have a theory then it is supported by evidence that shows how the theory works and by prediction tests that have been made. Even if you have an hypothesis in science you need to be able to show how it explains the existing evidence.
Before it was tested e = mc2 was just an hypothesis, one that explained the difference between the observed orbit of Mercury and the one calculated by Newton's theory of gravity.
Enjoy

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(1)
Message 138 of 142 (823259)
11-08-2017 11:36 AM


Summary compilation of the topic information to date -- a few lines for Starman
A "uranium halos for dummies" condensed version.
Message 1 laid out the initial premise:
... from Dr Wiens:
Radiometric Dating
quote:
13. "Radiation halos" in rocks prove that the Earth was young.
This refers to tiny halos of crystal damage surrounding spots where radioactive elements are concentrated in certain rocks. Halos thought to be from polonium, a short-lived element produced from the decay of uranium, have been found in some rocks. ...
At any rate, halos from uranium inclusions are far more common. Because of uranium's long half-lives, these halos take at least several hundred million years to form. Because of this, most people agree that halos provide compelling evidence for a very old Earth.
(bold added for empHASis, part deleted not about uranium halos)
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 isotopes decaying into other isotopes by alpha decay, the energy of the alpha particle is unique to that decay stage because of the unique before and after mass of the decaying isotope and the constant mass of the alpha particle.
This unique energy then determines how far (on average) an alpha particle will travel before it gets stopped and absorbed into the surrounding material (and 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 more than one particle to form as each one only makes a point on the ring. Thus uranium, with it's long half-life, takes "several hundred million years to form."
Now the fun part: this is based on our knowledge of physics and the physical constants that tell us how things behave in the universe, so what happens if you have fast decay instead of old time?
... Alpha Decay, Alpha detectors and identification:
quote:
However, if the alpha has enough energy to surmount this barrier then it will regain that energy as electrostatic repulsion once it gets outside the range of the attractive strong nuclear force. One important consequence of this is that all alpha emissions have at least ~5 MeV energy. Furthermore, half-life is inversely related to decay energy.
(bold for empHASis)
Very simply put, if you change the decay rate, you change the decay energy, and the diameter of the halo changes.
There should be no characteristic uranium halos with the unique energy of uranium alpha decay from fast decay.
The existence of (common) uranium halos then is evidence that shows the physical constants have not changed while they were formed, and their formation in turn is evidence that the earth is old, at least several hundred million years old.
Message 3 adds information on the physical process for how the halos are made:
article abstract The nature of radiohaloes in biotite: Experimental studies and modeling:
quote:
... Radiohaloes in biotite resulted from the impact of 4He cores (α-particles) emitted from actinide-bearing inclusions. Monte Carlo simulations yielded α (238U, 235U, and 232Th series) penetration ranges in biotite between 12.5 and 37.3 μm, which are in reasonable agreement with the observed radii of radiohaloes in natural biotites. The coloration pattern of a radiohalo closely correlates with the calculated distribution pattern of point defects generated in displacive events. Calculated point defect densities in the range from < 10-5 to at most 10-2 dpa (displacements per lattice atom) suggest that there are only scattered point defects in a mainly preserved biotite lattice. ...
(bold for empHASis)
SO the ring would be caused by the alpha particle causing a "point defect" in the surrounding material, interrupting the normal light pattern
And it takes a lot of those single point impacts at the same decay energy distances from the core to accumulate over time into a visible halo.
See Message 3 for more complete quote of the abstract.
Message 5 presents some of the mechanics of alpha decay:
... article on the forces in a nucleus and how that affects decay:
The Strong Nuclear Force, Alpha Decay and Fission
quote:
Unlike the electric forces, whose strengths are given by the simple Coulomb force law, there is no simple formula for how the strong nuclear force depends on distance. Roughly speaking, it is effective over ranges of ~1 fm, but falls off extremely quickly at larger distances (much faster than 1/r2). Since the radius of a neutron or proton is about 1 fm, that means that when a bunch of neutrons and protons are packed together to form a nucleus, the strong nuclear force is effective only between neighbors.
In a very heavy nucleus, (c), a proton that finds itself near the edge has only a few neighbors close enough to attract it significantly via the strong nuclear force, but every other proton in the nucleus exerts a repulsive electrical force on it. If the nucleus is large enough, the total electrical repulsion may be sufficient to overcome the attraction of the strong force, and the nucleus may spit out a proton. Proton emission is fairly rare, however; a more common type of radioactive decay in heavy nuclei is alpha decay, shown in (d). The imbalance of the forces is similar, but the chunk that is ejected is an alpha particle (two protons and two neutrons) rather than a single proton.
It is also possible for the nucleus to split into two pieces of roughly equal size, (e), a process known as fission.
This is just background information ...
Message 7 adds to the mechanics of alpha decay and includes the inverse relationship of alpha particle energy to isotope half-life:
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.
Why an alpha particle and not a proton?
Alpha Binding Energy
quote:
The nuclear binding energy of the alpha particle is extremely high, 28.3 MeV. It is an exceptionally stable collection of nucleons, and those heavier nuclei which can be viewed as collections of alpha particles (carbon-12, oxygen-16, etc.) are also exceptionally stable. This contrasts with a binding energy of only 8 MeV for helium-3, which forms an intermediate step in the proton-proton fusion cycle.
I envisage it as a pyramid with each particle in contact with the other, and therefore bound by the strong force.
Message 8 provides the crux of the process:
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. Not a strict inverse relationship (exponential?)
Message 9 provides some formulas:
PHYS 490/891 - Winter 2007, 2.8 Alpha-Decay
quote:
Qα = Eb(Z, A) - Eα(Z - 2, A - 4) - Eα(2,4) .
Now the we can translate the above condition for the possibility of an α-decay to Qα > 0. Fig. 14 shows a diagram with Qα-values for β-stable nuclei. Positive values start to appear for A > 150.
While the energy range of alpha-decays observed in nature is relatively narrow (~ 2 - 12 MeV) the lifetimes span a range from 10 ns to more than 10^19 years. To better understand this behaviour we will investigate the mechanism of this decay a little closer.
...
So we find for the decay constant:
λ = wαvαe-G/2R

Message 82 adds more information:
CF210: Constancy of Radioactive Decay Rates
quote:
# The half-lives of radioisotopes can be predicted from first principles through quantum mechanics. Any variation would have to come from changes to fundamental constants. According to the calculations that accurately predict half-lives, any change in fundamental constants would affect decay rates of different elements disproportionally, even when the elements decay by the same mechanism (Greenlees 2000; Krane 1987).
Which means that the radii of the different halos for the different daughter isotopes would change by different amounts - yet this is not observed in the Uranium halos .... and therefore Uranium halos are indeed evidence that the earth is very old.
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.
You need to invoke different magic alteration of the physical constants for each isotope to end up with the observed results, which are in agreement with the predictions from the calculations.
Now I am going to include Message 90 because the argument from Smooth Operator is similar to the argument from Starman:
Uranium halos are not evidence for an old Earth because they are based on two assumptions you don't know anything about. So let's take it step by step...
1.) Half life of U238.
1.) The claim that U238 half-life is 4.5 billion years. How do you know that? Where has this been shown to be true? You don't know that. You assume that. And since you don't know it, you don't know that it took 4.5 billion years to make ANY U238 halo.
This denial of reality is based on both a logical fallacy (argument from incredulity) and general logically false thinking. The astute reader will note that Smooth Operator did not provide any evidence of a different decay rate, he just employed the PRATT that because event X was not observed we can know nothing about event X.
Curiously, the claim that Uranium Halos are evidence of extreme age for the earth comes from a scientist who does in fact know a whole heck of a lot more about the physics involved than Smooth Operator has demonstrated (he can't even get the facts right):
Radiometric Dating
quote:
At any rate, halos from uranium inclusions are far more common. Because of uranium's long half-lives, these halos take at least several hundred million years to form. Because of this, most people agree that halos provide compelling evidence for a very old Earth.
Not just the 238U half-life, but the half-life of several of the decay products as well.
Amusingly, one does not need to observe a radioactive material for the full length of the half-life in order to measure the decay rate, as the physics involved follows very predictable paths.
If Smooth Operator's claim were true we would not know the half-life of a single element with a half-life over 50 years, while curiously, the half-lives of almost all elements are known to a high degree of precision.
Not only do we have the initial information of decay curves to provide the slopes at the beginning of exponential curves actively defining the half-life for the elements, we have parent-daughter relationships that show that the proportions of elements found does in fact correlate with the measured half-lives.
Radioactive dating methods also correlate and confirm each other, even though they are derived from materials with different half-lives and therefore different proportions of the various elements at different ages.
One example of such correlations is found with the Oklo evidence.
http://oklo.curtin.edu.au/
Another example of this is the correlation of radiocarbon dating with both annual tree rings and with organic specimens from the varves in Lake Suigetsu, showing that 14C dating methods do in fact represent the age of the specimens, because we know their age by other means, means that are more accurate than 14C (due to atmospheric variations in 14C) and which can be used to correct for the atmospheric fluctuations in the past.
However, to more fully discuss radioactive decay and dating systems that are based on this concept we would prefer a system not subject to this kind of variation seen with 14C. We also need one that can be correlated over substantial time to validate the system.
Such an example is found in
USGS URL Resolution Error Page (8)
quote:
In 1997, the Devils Hole Thorium-230 dates were independently confirmed by non-USGS investigators using Protactinium-231.
(See Broecker, 1992; Ludwig, et al., 1992; Winograd, et al., 1997; and Edwards, et al., 1997.)
Corroborated by two independent radiometric methods. The oldest date in the data table is 567,700 years ago.
So what exactly do we have here? Water dripping down a cave wall, depositing calcite and various other minerals and impurities, elements that are soluble in water, including trace levels of radioactive isotopes of uranium. Material that gets deposited with the calcite formation as the water evaporates, forming layer after layer of similar deposits, each one trapping the material in their respective layers. The calcite forms a matrix that holds the impurities, minerals and trace elements in a position related to the time the calcite was deposited.
The calcite is deposited year by year, with the soluble elements being trapped as the water evaporates, and thus dating the layers radioactively by the measurement of the relative amounts of non-soluble elements that are derived by radioactive decay of soluble radioactive elements.
In this case two independent radioactive elements, Thorium and Protactinium.
Radiometric Dating (9)
quote:
Two of the most frequently-used of these "uranium-series" systems are uranium-234 and thorium-230.
... The chemistry of uranium and thorium are such that they are in fact easily removed from each other. Uranium tends to stay dissolved in water, but thorium is insoluble in water. So a number of applications of the thorium-230 method are based on this chemical partition between uranium and thorium. ...
Comparison of uranium-234 ages with ages obtained by counting annual growth bands of corals proves that the technique is highly accurate when properly used (Edwards et al., Earth Planet. Sci. Lett. 90, 371, 1988). The method has also been used to date stalactites and stalagmites from caves, already mentioned in connection with long-term calibration of the radiocarbon method. In fact, tens of thousands of uranium-series dates have been performed on cave formations around the world.
http://www.ead.anl.gov/pub/doc/protactinium.pdf (5)
quote:
Protactinium-231 is a decay product of uranium-235 and is present at sites that processed uranium ores and associated wastes. This isotope decays by emitting an alpha particle with a half-life of 33,000 years to actinium-227, which has a half-life of 22 years and decays by emitting an alpha or beta particle.
The U-235 to Pa-231 decay is from a different series than the U-234 to Th-230 decay, so the two are independent of each other. Again, as the Devil's Hole calcite was deposited after being dissolved in water, the Pa-231 in the calcite could only come from the decay of the parent U-235, giving an accurate measurement of the age of the layers of calcite.
Exponential decay - Wikipedia (4)
quote:
A more intuitive characteristic of exponential decay for many people is the time required for the decaying quantity to fall to one half of its initial value. This time is called the half-life, and often denoted by the symbol t1/2. The half-life can be written in terms of the decay constant, or the mean lifetime, as:
t1/2 = ln2/λ = Tln2

When this expression is inserted for T in the exponential equation above, and ln2 is absorbed into the base, this equation becomes:
N(t) = N02-t/t1/2

Using the half-lives of thorium-230 (75,380 years) and protactinium-231 (32,760 years), we can now draw the exponential curves for these isotopes (with % on the y-axis and time in k-yrs on the x axis, thorium in blue and protactinium in red):
This means we have a series of data with three different pieces of information: calcite layer age by relative depth in the formation, and Thorium-230 content and Protactinium-231 content in each layer. We also note that Thorium-230 has a half-life of 75,380 years, while Protactinium-231 has a half-life of 32,760 years - less than half the half-life of Thorium-230. This means that layer by layer the ratio of Thorium-230 to Protactinium-231 is different:
   Age   THr=THf/THo PAr=PAf/PAo  THr/PAr
---------------------------------------------
75,380 0.5000 0.2029 2.46
150,760 0.2500 0.0412 6.07
226,140 0.1250 0.0084 14.96
301,520 0.0625 0.0017 36.86
376,900 0.0313 0.0003 90.82
452,280 0.0156 0.0001 223.77
527,660 0.0078 0.00001 551.350
So for these dates to be invalid there would have to be a mechanism that can layer by layer preferentially change the ratio of these two {elements\isotopes} within the solid calcite vein.
Rather than just wave his hands in denial, Smooth Operator -- or anyone else trying to deny this evidence -- would have to show some reasonable method to achieve these different ratios by some other system.
This validates radioactive decay rates for the 567,000 year duration of this evidence, and confirms the half-lives for each of these isotopes.
In other words, we can have a high degree of confidence in the measured decay rates of the various elements involved from the multiple sources of information and from the correlations of information that validate these rates.
2.) Halo itself.
2.) And the second assumption, which is even worse. Is the assumption that the U238 halo was produced by a constand decay rate. And then you turn and say that since it was constant decy, it had constant energy, thus a specific halo was formed that can only be produced by constant energy. That's circular logic. Since you don't know by what energy strength was that halo formed, you don't know if it was formed by constant decay, and of course constant energy. And you don't know that, because you never saw a U238 halo form, and what energy it took to form the said halo, that you never saw form in the first place.
Again, Smooth Operator is missing the vital element of this issue: the alpha decay energy needs to be constant for the halos to form, as the diameter of the halo for each different isotope in the decay series is fixed by the unique alpha decay energy for that isotope.
Nobody needs to observe the halo being formed to see that the result is due to the alpha decay energies being the same for each isotope in the series over a period of time long enough for all the alpha decay events to have occurred.
Due to the physics involved, decay energy, whether alpha or beta, is related to the half-life of the particular isotope. Each isotope that decays by alpha decay has a unique alpha decay energy specific to that kind of decay event. This physics also shows that if you change the decay rate that this results in change to the alpha energy.
Further the physics shows that any change to the basics of decay will affect different isotopes to different degrees, so the change to one isotope's alpha decay rate\energy will be different from the change to another isotope's alpha decay rate\energy.
Thus the problem that needs to be explained is how all these decay events actually occurred with the precise alpha energy to form the halos if the decay rates were different. Each isotope decay rate change needs to be "juggled" in a different degree to explain the evidence of the halos.
Saying that there is evidence of decay rate changes (even if true) and saying that there is evidence of alpha energy changes (also even if true) does not show how this is coordinated to produce the halo at the correct diameter.
One needs to complete an alternate explanation that fully explains all the evidence, not just denial of the explanation provided by physics, the halos, and an old age for the earth.
Smooth Operator has not done this. His premises are false, and therefore all his conclusions are invalid.
I have no interest in debating Smooth Operator further on this issue, until he can show how each precise alpha decay energy can be produce by some other method, and demonstrate that decay rates can be changed by factors of thousands while producing the same alpha decay energy. He can start another thread to do this.
and the final bit I want to include in this summary is from Message 99:
Gamow factor - Wikipedia
quote:
The Gamow Factor or Gamow-Sommerfeld Factor[1], named after its discoverer George Gamow, is a probability factor for two nuclear particles' chance of overcoming the Coulomb barrier in order to undergo nuclear reactions, for example in nuclear fusion. By classical physics, there is almost no possibility for protons to fuse by crossing each other's Coulomb barrier, but when George Gamow instead applied quantum mechanics to the problem, he found that there was a significant chance for the fusion due to tunneling.
This probability increases rapidly with increasing particle energy, but at a given temperature the probability of a particle having a high energy falls off rapidly, following the Maxwell-Boltzmann distribution. Gamow found that, taken together, these effects mean that for any given temperature, the particles that actually fuse are mostly in a (temperature-dependent) narrow range of energies known as the Gamow window.[2]
Oh look, I found this by googling gamow decay energy calculation
http://www.phy.uct.ac.za/courses/phy300w/np/ch1/node38.html
quote:
... (several formulas with undefined symbols, have fun) ...
The Geiger-Nutall equation is thus recovered. Note the extreme sensitivity of the decay constant on the energy in the above equation.
Change the decay rate and you change the energy of the decay particle.
and
(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.
There you have it -- a direct link between decay energy and the half-life of the isotopes.
Note that this is not a linear function, so doubling the decay rate results in different decay energies of the alpha particles from different isotopes and they don't have the same ratios one to the next as we observe with today's decay rates.
Link this with the large number of decay events needed to form a visible halo and it is clear that these constants have not changed during the formation of the uranium halos
Enjoy
Edited by RAZD, : .
Edited by RAZD, : .

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