Uranium Halos--decay constants...constant

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
Please note that this thread is NOT about polonium halos, nor is it about uranium dating. Any reference to those topics will be considered off topic and ignored. We can discuss those in another thread, if you like, but I want to focus on this topic, please.

As Uranium 238 decays through alpha-decay, the emitted alpha particles create damage to the surrounding rock, forming a sphere around the inclusion whose radius is dependent on the alpha particle decay energy.

They are called halos because we study them by looking at cross-sections of the sphere.

Now, it takes many decay events to form this visible sphere, since each atom that decays only produces one dot on the sphere. Something like 10^9 atoms of uranium need to decay in order to produce this sphere.

Since the half life of Uranium is about 4.5 billion years, in order for enough atoms to decay to form a halo, it would take hundreds of millions of years.

This is evidence of an old earth.

But there is more, it's also evidence that the decay constant of Uranium 238 has been constant for that time. Why?

Because the decay rate is inversely related to the decay energy. So, if the decay rate was faster in the past, the halo radius would be a different size. So, since the Uranium halos have a radius consistent with the decay energy that we observe today, we know that decay rates have not changed for hundreds of millions of years.
 

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
Well of course, there is no logical reason that element behavior would be different in the past than it is now, unless you go back to before the Big Bang.

Changing decay constants is one of the arguments that creationists use to demonstrate that we are making "assumptions" so that they can handwave our arguments away.
 
Upvote 0

PsychoSarah

Chaotic Neutral
Jan 13, 2014
20,521
2,609
✟95,463.00
Faith
Atheist
Marital Status
In Relationship
Changing decay constants is one of the arguments that creationists use to demonstrate that we are making "assumptions" so that they can handwave our arguments away.

Which is one of the least logical arguments I see people present.
 
Upvote 0

Freodin

Devout believer in a theologically different God
Mar 9, 2002
15,711
3,761
Germany, Bavaria, Middle Franconia
Visit site
✟242,764.00
Faith
Atheist
[dad]But you cannot show that the laws of physics were different in exactly the way to produce this same halos with faster decay speeds in previous times or in places far away. Therefore...[/dad]

Which of course is an even less logical argument... if that is even possible.
 
Upvote 0

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
[dad]But you cannot show that the laws of physics were different in exactly the way to produce this same halos with faster decay speeds in previous times or in places far away. Therefore...[/dad]

Which of course is an even less logical argument... if that is even possible.

Yes, quite the deceptive god he believes in.
 
Upvote 0

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
Nice job 46.......

It's not something I came up with...but it's an extremely strong argument, and has the added benefit of not being often tackled by professional apologists. So creationists are left with two options, ignore it, or actually research it for themselves for once....
 
Upvote 0

essentialsaltes

Stranger in a Strange Land
Oct 17, 2011
32,801
36,095
Los Angeles Area
✟820,272.00
Country
United States
Faith
Atheist
Marital Status
Legal Union (Other)
So, since the Uranium halos have a radius consistent with the decay energy that we observe today, we know that decay rates have not changed for hundreds of millions of years.

You could possibly jigger a bunch of other parameters (electric charge, nucleon radius, etc.) to keep your U-238 halo the same size while changing the decay rate, but even disregarding the havoc that would cause, the existence of several different isotopes that produce halos shows that your argument is correct. You would not be able to juggle the constants to keep all of them the 'right' size simultaneously.
 
Upvote 0

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
You could possibly jigger a bunch of other parameters (electric charge, nucleon radius, etc.) to keep your U-238 halo the same size while changing the decay rate, but even disregarding the havoc that would cause, the existence of several different isotopes that produce halos shows that your argument is correct. You would not be able to juggle the constants to keep all of them the 'right' size simultaneously.

I don't think you can even do that. The energy of the alpha particle is based on the stability of the decaying atom. If you speed up the decay rate (make it more unstable), then you increase the energy of the alpha particle and make a bigger halo.
 
Upvote 0
This site stays free and accessible to all because of donations from people like you.
Consider making a one-time or monthly donation. We appreciate your support!
- Dan Doughty and Team Christian Forums

Loudmouth

Contributor
Aug 26, 2003
51,417
6,141
Visit site
✟98,005.00
Faith
Agnostic
You could possibly jigger a bunch of other parameters (electric charge, nucleon radius, etc.) to keep your U-238 halo the same size while changing the decay rate, but even disregarding the havoc that would cause, the existence of several different isotopes that produce halos shows that your argument is correct. You would not be able to juggle the constants to keep all of them the 'right' size simultaneously.

As you or perhaps others have mentioned, it is rather curious to see creationists changing the parameters of the four fundamental forces all willy nilly in order to explain radiometric dating, and then have them turn around and explain how finely tuned those very forces have to be in order for life to exist.

It's as if the right hand can not see with the left hand is doing.
 
Upvote 0

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
As you or perhaps others have mentioned, it is rather curious to see creationists changing the parameters of the four fundamental forces all willy nilly in order to explain radiometric dating, and then have them turn around and explain how finely tuned those very forces have to be in order for life to exist.

It's as if the right hand can not see with the left hand is doing.

Indeed. And they don't think about what those changes would mean. In this example, if you changed the parameters necessary to account for a young earth, you'd have elements weighing ridiculous amounts, or gravity too weak to hold the solar system together, or...
 
Upvote 0

Seipai

Regular Member
Jan 20, 2014
954
11
✟1,266.00
Faith
Lutheran
Marital Status
Single
As you or perhaps others have mentioned, it is rather curious to see creationists changing the parameters of the four fundamental forces all willy nilly in order to explain radiometric dating, and then have them turn around and explain how finely tuned those very forces have to be in order for life to exist.

It's as if the right hand can not see with the left hand is doing.


All creationist claims are inevitably self refuting. That is why "Flood Geology" is such a joke. Sooner or later reality gets in the way.
 
Upvote 0

CaceyKing

Junior Member
Feb 8, 2014
36
0
England
✟15,156.00
Faith
Atheist
Marital Status
Single
As Uranium 238 decays through alpha-decay, the emitted alpha particles create damage to the surrounding rock, forming a sphere around the inclusion whose radius is dependent on the alpha particle decay energy.

They are called halos because we study them by looking at cross-sections of the sphere.

Now, it takes many decay events to form this visible sphere, since each atom that decays only produces one dot on the sphere. Something like 10^9 atoms of uranium need to decay in order to produce this sphere.

Since the half life of Uranium is about 4.5 billion years, in order for enough atoms to decay to form a halo, it would take hundreds of millions of years.

This is evidence of an old earth.

But there is more, it's also evidence that the decay constant of Uranium 238 has been constant for that time. Why?

Because the decay rate is inversely related to the decay energy. So, if the decay rate was faster in the past, the halo radius would be a different size. So, since the Uranium halos have a radius consistent with the decay energy that we observe today, we know that decay rates have not changed for hundreds of millions of years.

Thank you for this post. As much as I want to sit back and put my feet up saying "There we've gotten through to the Creationist" there are a variety of issues they could nitpick at.

One such nitpick I foresee by the slightly more Scientific Literate Creationists, a contradiction of terms perhaps, is that Radioactive Decay is determined by probability as Quantum Theory states, such as the Schrodinger's Cat analogy, it's impossible to attempt to predict exactly when any particular atom will decay.

So I've decided to play my part and take the time, currently 12:00, to provide some of the Mathematics behind Radioactive Decay as best as I can. I doubt I can provide it all though.

You referred to "Half-Life" so I'll elaborate on that.

The Half-Life is the time taken for half of the Radionuclide to decay. A Radionuclide is an Atom with an unstable Nucleus. A Nucleus being the center of an Atom consisting of Protons and Neutrons which are Subatomic Particles. Radioactive Decay is the process where the Nucleus of an unstable Atom, a Radionuclide, loses energy by emitting Particles of Ionizing Radiation. Ionizing Radiation is Particles that carry enough Kinetic Energy to liberate an Electron, Subatomic Particles that orbit the Nucleus, from an Atom or Molecule ionizing it.

So with that out of the way here is the some of the Maths surrounding it but be mindful of the limitations of the font.

N = N0e¯λt = N0e¯λt/τ

N is the number of Nuclides or Nuclide Population.

A Nuclide is a Atom or Nucleus characterized by the specific number of Protons and Neutrons.

For example Uranium-238 is an Isotope. All Isotopes can have the same number of Protons but can differ in number of Neutrons.

Essentially the equation breaks down as N(Nuclide Population) = N0e¯λt and the t = τ1/2 where λ is the Decay Constant and τ is the Time Constant. N0 is the value of N at time t = 0 and where e¯ means Electons as far as I can tell.

I'm am by no means an expert on Mathematics especially on what means what when it comes to complicated equations like this one. It is now 13:00 and as you might be able to tell there are still a lot to explain of what this equation means and how it works. As well as there being many complimentary or outright necessary additional equations involved. For example the one for obtaining τ1/2 which I think is the Half-Life itself. But this specific one is impossible to right with the limitations of the font system on this forum. I've also spent an hour doing a lot of work on your behalf, on behalf of the Creationist that is, so it isn't unreasonable for you to have a little look into it yourself.

I hope this is appreciated. This is obviously not a solid explanation, probably not even a solid equation I have no idea to be honest, but if anyone wants to they can elaborate on what I've said. There also might be room for correction as I honestly think I bit off more than I could chew as they say.

I'm going to have to learn all this properly sometime.
 
Last edited:
Upvote 0
This site stays free and accessible to all because of donations from people like you.
Consider making a one-time or monthly donation. We appreciate your support!
- Dan Doughty and Team Christian Forums

essentialsaltes

Stranger in a Strange Land
Oct 17, 2011
32,801
36,095
Los Angeles Area
✟820,272.00
Country
United States
Faith
Atheist
Marital Status
Legal Union (Other)
Essentially the equation breaks down as N(Nuclide Population) = N0e¯λt and the t = τ1/2 where λ is the Decay Constant and τ is the Time Constant. N0 is the value of N at time t = 0 and where e¯ means Electons as far as I can tell.

The e- is actually part of the exponential function. Writing it a bit differently the equation is

N = N0 * exp(-λt)

Where exp(x) is the exponential function. It's just a coincidence that the minus sign next to the e makes it look like 'an electron'.


To make the connection to the OP. A common YEC argument is to say that λ, the decay constant, is not actually constant. The OP notes that if λ changes, it would have effects on other observations (in this case, the size of radiohaloes in geological specimens). These effects are not observed; therefore, this gives us confidence that the decay constant really is a constant.
 
Upvote 0

CaceyKing

Junior Member
Feb 8, 2014
36
0
England
✟15,156.00
Faith
Atheist
Marital Status
Single
The e- is actually part of the exponential function. Writing it a bit differently the equation is

N = N0 * exp(-λt)

Where exp(x) is the exponential function. It's just a coincidence that the minus sign next to the e makes it look like 'an electron'.


To make the connection to the OP. A common YEC argument is to say that λ, the decay constant, is not actually constant. The OP notes that if λ changes, it would have effects on other observations (in this case, the size of radiohaloes in geological specimens). These effects are not observed; therefore, this gives us confidence that the decay constant really is a constant.

Thanks. That's quite an error on my part. When I looked into what "e¯" meant I couldn't find anything so what resulted was "e¯" being assumed to have something to do with Electrons. I assume the "e" is actually separate to the "¯" and this would have been obvious to me if I was a little more Mathematically Literate.

I kind of just went at a pointless tangent. Although I learnt something so I wouldn't call it pointless. Maybe somebody else learnt something too.
 
Upvote 0

dad

Undefeated!
Supporter
Jan 17, 2005
44,904
1,261
✟25,524.00
Country
Canada
Faith
Christian
Marital Status
Private
Since the half life of Uranium is about 4.5 billion years, in order for enough atoms to decay to form a halo, it would take hundreds of millions of years.

This is evidence of an old earth.
.
Not at all. This is evidence you believe that what goes on now represents what went on long ago. Obviously.
 
Upvote 0
This site stays free and accessible to all because of donations from people like you.
Consider making a one-time or monthly donation. We appreciate your support!
- Dan Doughty and Team Christian Forums

46AND2

Forty six and two are just ahead of me...
Sep 5, 2012
5,807
2,210
Vancouver, WA
✟102,103.00
Faith
Atheist
Marital Status
Single
Politics
US-Others
Not at all. This is evidence you believe that what goes on now represents what went on long ago. Obviously.

No dad...I went on to describe why we know it went on long ago...if it didn't go on long ago, the sphere would be of different radius.
 
Upvote 0