analyzing the dating systems

[archaeologist]

If %50 is gone in the first x time, please tell us what is left ?, and given that in the next x time %50 of what is left will decay, how much is that ?

you are not getting it. your formula:

100% - 50% = 50%
50% - 50% = 25%

what is being said is the amount of carbon atoms decaying decreases each half-life yet no one can provide a good reason or explanation why that change takes place or why it would take place.

in all my studies, i have never come across any explanation for this event and i have searched for libby's explanations but so far i either belong to the wrong libraries or the articles i can get to do not address this issue.

so by your insults and the re-telling what i have already studied or know, you are saying there is no explaination for this or you just accept this system on blind faith thinking that because scientists have thought it up, it must be correct (you didn't investigate it in other words).

 

[KerrMetric]

Why bother with this thread archeologist.

You obviously don't understand the concept of flipping a coin which is really all that is required here.

When someone goes 1/2 of a sample decayed in X years therefore the rest decays in the next X years there is really no point in trying to talk on this topic.

By your (il)logic no sample could ever go beyond 2 half lives. This is hilarious and sad and the same time OR you are a parody poster.

 

[KerrMetric]

you are not getting it. your formula:

100% - 50% = 50%
50% - 50% = 25%

what is being said is the amount of carbon atoms decaying decreases each half-life yet no one can provide a good reason or explanation why that change takes place or why it would take place.

Just embarrassing. Notice how no other creationist has stepped in. That's not because they aven't realised his error it's because they hat to be seen to correct their brethren.

in all my studies, i have never come across any explanation for this event and i have searched for libby's explanations but so far i either belong to the wrong libraries or the articles i can get to do not address this issue.

Staggers the mind that someone can be typing this.

so by your insults and the re-telling what i have already studied or know

, you are saying there is no explaination for this or you just accept this system on blind faith thinking that because scientists have thought it up, it must be correct (you didn't investigate it in other words).

What blind faith? You have been told repeatedly what is going on and it obviously cannot sink in.

This is high school science.


<staff edit>

 

[Deamiter]

you are not getting it. your formula:

100% - 50% = 50%
50% - 50% = 25%

what is being said is the amount of carbon atoms decaying decreases each half-life yet no one can provide a good reason or explanation why that change takes place or why it would take place.

Yes, it's always been said that the amount of atoms decaying depends on the CURRENT number of atoms, not the initial number of atoms. The atoms don't care how many were there a half-life ago, each one that exists NOW has a 50% chance of having decayed once another halflife has passed.

Again, the NUMBER decreases because the PERCENTAGE stays the same. The same percentage of existing atoms decays during the same amount of time.

So the equations above should be reducing by fifty percent each time, not fifty percent of the INITIAL amount.

100/2 = 50%.
50/2 = 25%
25/2 = 12.5%
etc...

Because only 50% of the atoms exist after the first halflife, there are only 50% of atoms left to decay during the second half-life so only 50% of the existing 50% will decay -- hence 25%.

 

[archaeologist]

Deamiter's & metherion's reply came in while i was typing a response to those who look to insult and defy the original post. par for the course.
<staff edit>

In a single half-life, every single atom has a 50% chance of decaying. Half of them will decay and half won't. Now in two half-lives, you don't reach a 100% chance of decaying. During the first half-life, each atom has a 50% chance of decaying. During the second half-life each atom has a 50% chance of decaying, but since there are fewer atoms, fewer will decay

sorry i was going to address both replies but i have class now and need to go. both replies do raise more questions which point out problems with the c-14 dating system and maybe, <staff edit>, these issues can be exploreed rationally and with respect

 

[Deamiter]

Deamiter's & metherion's reply came in while i was typing a response to those who look to insult and defy the original post. par for the course.

sorry i was going to address both replies but i have class now and need to go. both replies do raise more questions which point out problems with the c-14 dating system and maybe,, these issues can be exploreed rationally and with respect

You can never force other people to behave as you would like, you can only control your own actions. Christian Forums has a great ignore feature that you can use if you can't stand to avoid responding to off-topic remarks. I've always found that it's best to ignore insults and stick to the topic yourself as a thread can't be single-handedly derailed! You're perfectly welcome (and very able) to ignore him either with self-control or with the ignore feature.

I've got two physics-based degrees and I can assure you that this exponential atomic decay is not just an assumption but is a solid conclusion. In at least three of my classes, we each performed experiments confirming this exponential decay so I'm not just trusting some academic. I'm not suggesting you always trust authorities, but in this case, I suggest you look closer at what you don't understand rather than continuing to claim that atomic decay should be linear. Again, it's not just an assumption or a theoretical equation but a model that was designed to directly explain observations. We know that the RATE (again not the number) of decay is constant because it is OBSERVED to be constant. Nothing but conditions so extreme to not be found in nature (hotter than the Sun for example) have been observed to change decay rates so again, it's not an assumption but a direct observation that the rates don't change.

 

[theIdi0t]

Again, this isn't just making stuff up, it's what is observed. For the record, the equation you cited is equivalent to the equations cited earlier in the thread -- they're just formed differently. And both forms of the equation will show you that decay is not linear, it's exponential. If you plug one halflife into either equation, you'll get 50% remaining. If you plug TWO halflives into the equation, you'll get 25% remaining. That's what's observed so that's what the equations used to model our observation are designed to show.

I apologize for my ignorance, I also know little about radiometric dating. I stay out of debates dealing with the subject. Nor have I learned the math behind it, so I'm not all that sure what the numbers in the formula equate to.

Can I compare it to this:

I start off with $100, and every six months I lose 50% of what I have. After the first six months I have $50 dollar remaining, and after another 6 months (a total of a year) I have 25$ remaining?

If I am correct this far, is this to say that the half-life is 6 months?

The thing that I am confused about is how do you know what the "starting amount is"? If I knew that the starting amount was $100, and at some point and I was left with only $12.50, I could figure out that it took 1 1/2 years for this to happen, but how do you determine the starting amount for the comparison?

Forgive me if I'm totally off base.

 

[peteos]

May I ask, Archaeologist, what school and what subject you are doing graduate studies in?

 

[KerrMetric]

I apologize for my ignorance, I also know little about radiometric dating. I stay out of debate dealing with them. Nor have I learned the math behind it, so I'm not all that sure what the numbers in the formula equate too.

Can I compare it to this:

I start off with $100, and every six months I lose 50% of what I have. After the first six months I have $50 dollar remaining, and after another 6 months (a total of a year) I have 25$ remaining?


If I am correct this far, is this to say that the half-life is 6 months?

Exactly.

The thing that I am confused about is how do you know what the "starting amount is"? If I knew that the starting amount was $100, and at some point and I was left with only $12.50 at a certain point, I could figure out that it took 1 1/2 years for this to happen, but how do you determine the starting amount for the comparison?

Forgive me if I'm totally off base.

Why on earth would you need the starting amount?

Just measure the number of decays versus time.

In other words in your analogy just measure the account debit. In the first 6 month you lost a measurable X dollars - next 6 months you lose X/2 dollars for a half life of 6 months.

You don't need to know the initial amount to work out the half life.

 

[KerrMetric]

May I ask, Archaeologist, what school and what subject you are doing graduate studies in?

Head scratcher isn't it?

 

[PFJ]

Well, maybe it is because they are. Far be it from me to comment, with only two years of science education at a highschool level, which I paid very little attention to, but the several thousand or so qualified scientsts who form the majority of the scientific community seem more trust worthy to me with claims that it is an accurate form of dating, then you.

 

[Rudolph Hucker]

Archie ol' boy, you and I have been cyber chums for 3 years or more now, but on this topic, please desist: you are in very deep here with some very knowledgeable and qualified fellows. I am feeling your embarrassment.

This time, ol' chap, why not walk away?

 

[theIdi0t]

Exactly.
Why on earth would you need the starting amount?

Just measure the number of decays versus time.

In other words in your analogy just measure the account debit. In the first 6 month you lost a measurable X dollars - next 6 months you lose X/2 dollars for a half life of 6 months.

You don't need to know the initial amount to work out the half life.

I wasn't trying to work out the half-life, but the amount of time it took me to reach $12.50.

If I know the starting amount is $100 then I know that I have been losing money for 1 1/2 years. But if I started off with only $25 and not a $100, then I've only been losing money for six months. But I can't determine with the $12.50 alone if I've been losing money for six months, or for 1 1/2 years.

I'm equating the time that I have been losing money to age.

I know that I'm missing something, I just haven't figured out what it is.

 

[KerrMetric]

I wasn't trying to work out the half-life, but the amount of time it took me to reach $12.50.

If I know the starting amount is $100 then I know that I have been losing money for 1 1/2 years. But if I started off with only $25 and not a $100, then I've only been losing money for six months. But I can't determine with the $12.50 alone if I've been losing money for six months, or for 1 1/2 years.

I'm equating the time that I have been losing money to age.

I know that I'm missing something, I just haven't figured out what it is.

OK - your analogy was a correct mathematical one for the decay law but this is not how actual dating is done.

When doing dating you just take a small sample and count the atoms of the parent and daughter atoms.

Parent decays to daughter.

Now for the moment assume that the sample originally began with 100% Parent but obviously after some time t it will be a mixture of Parent (P) and Daughter atom (D).

The age t is given by the following formula:

t = (T/ ln2)*ln(1+D/P)

So if you count the D and P in the sample and you know the half life T then you calculate the age.

Now this is in an ideal circumstance where you know originally D was 0 and P was 100%. In reality it is more complicated than this and I don't have space here to go into it. Google "isochronal dating methods".

EDIT - read this instead of Googling http://www.asa3.org/aSA/resources/Wiens.html


By the way in your example:

D = 87.5
P = 12.5
T = 6 months

which gives t = 18 months using the above formula which is of course the correct 3 half lives.

 

[metherion]

Well, theIdi0t, you seem to have the decay part down.

The thing is, you're confused as to finding the initial point.

At least as I understand it.

Well, it works like this.

Decaying atoms throw things off. That's radiation. After the atom throws something off, it becomes something else. An easy example is alpha particle emission. An alpha particle has 4 neutrons and 2 protons. (Pretty much, it is a very energetic helium nucleus with no electrons.) This next bit is NOT AN ACTUAL DECAY, just an example.

Let's say oxygen encased in rock (so it and it's radiation can't get out) emits an alpha particle. This would take oxygen from having a molecular weight of 16 to having one of 10, and from having 8 protons to having 6. That would make Carbon-10. (again, this does not happen. I'm just pulling elements out of thin air [pun intended] to show you what I mean). So, we can figure out just how long oxygen has been decomposing by measuring carbon 10.

So, let's go back to your debit card analogy. Every purchase you made went to another account to buy euros. If we can find that other account, we can figure out how much you started with by finding out how many euros you bought with your dollars. So if you had 187.50 euros (and you managed to find a 1-1 dollar-euro exchange) we could tell you started with 200$.

Does that help at all?

Metherion

Edit:

POST NUMBER ONE THOUSAND WOOHOO! *happy dance*

 

[theIdi0t]

By the way in your example:

D = 87.5
P = 12.5
T = 6 months

which gives t = 18 months using the above formula which is of course the correct 3 half lives.

I see the error, I took decay to mean disappearing rather than transforming. I assumed that the 87.5 dollars disappeared rather than transformed, i.e. carbon-14 (parent) transforms into nitrogen-14 (daughter).

I appreciate the input, I guess I still have much more to learn.

 

[theIdi0t]

Does that help at all?

Yea, I ran into "radioactive decay" on wikipedia, and I saw what I was missing.

 

[pgp_protector]

I apologize for my ignorance, I also know little about radiometric dating. I stay out of debates dealing with the subject. Nor have I learned the math behind it, so I'm not all that sure what the numbers in the formula equate to.

Can I compare it to this:

I start off with $100, and every six months I lose 50% of what I have. After the first six months I have $50 dollar remaining, and after another 6 months (a total of a year) I have 25$ remaining?

If I am correct this far, is this to say that the half-life is 6 months?

The thing that I am confused about is how do you know what the "starting amount is"? If I knew that the starting amount was $100, and at some point and I was left with only $12.50, I could figure out that it took 1 1/2 years for this to happen, but how do you determine the starting amount for the comparison?

Forgive me if I'm totally off base.

Think of it this way.
You have 1000 green marbles 0 Blue Marbles
in x units of time 50% will turn blue (decay)
in 1 x unit of time you have 500 Green 500 Blue.
in 2 x units of time you have 250 Green 750 Blue.
in 3 x units of time you have 125 Green 875 Blue

So if you know the total amount of marbles in your sample (Green + Blue) and the 1/2 life. and the ratio of Green to Blue, you can then compute the age of the sample (how long it's taken to go from all Green to 2 Green 998 blue)

 

[archaeologist]

I've got two physics-based degrees

not challenging your education, i am sure your are very qualified.

but in this case, I suggest you look closer at what you don't understand rather than continuing to claim that atomic decay should be linear

i am just exploring an angle at the moment.

We know that the RATE (again not the number) of decay is constant because it is OBSERVED to be constant.

so you are talking about the time or the percentage?

it's not an assumption but a direct observation that the rates don't change.

even so, if 50% go in the first half-life, what changes affect the remaining atoms that fewer decay than those in the first?

your explaination there are fewer atoms so fewer decay doesn't cut it because the amount of atoms should not determine how many decay.

idiot:

I start off with $100, and every six months I lose 50% of what I have

{bold mine} except they are not describing it wth those words. they say that every 5700 years +/- 50% decay and that indicates a change in the process. your phrasing indicates a constant that doesn't change.

metherion:

Every purchase you made went to another account to buy euros. If we can find that other account, we can figure out how much you started with by finding out how many euros you bought with your dollars. So if you had 187.50 euros (and you managed to find a 1-1 dollar-euro exchange) we could tell you started with 200$

except relating that to dating means you still do not know how old an artifact is because the intake may not be constant over a given life time.

thus the assumed total may be more or less than the actual age leaving everyone at square one asking, 'how old is it really?'

 

[theIdi0t]

{bold mine} except they are not describing it wth those words. they say that every 5700 years +/- 50% decay and that indicates a change in the process. your phrasing indicates a constant that doesn't change.

I thought they described it quite well, in those words.

I'm confused at what constant that doesn't change are you referring to. The half-life of 6 months, or the amount I had at the begining?

If it's the latter then I assume it would be the current amount of green marbles + blue marbles (referring to pgp_protector's post).
Or the dollar value of euros + the dollars I have remaining (referring to Metherion's post). Or parent atoms + daughter atoms = starting amount of parent atoms (referring to Kerrmetric's post).