Anybody understand equilibrium?

[FallingWaters]

I don't understand the reason why the C-14/C-12 must be working toward equilibrium. How do we know that equilibrium can even be attained? What principle of science is this based on?

Apparently, C14 dating was originally developed based on the assumption that C14 and C12 were in equilibrium. It turns out that our atmosphere is 25% OUT of equilibrium. Not only that, but it turns out that nuclear testing alters C14/C12 readings.

I don't see how can we develop any scientific testing method on an equilibrium that doesn't exist and may never exist.

What says we must have equilibrium? What law?

 

[juvenissun]

I don't understand the reason why the C-14/C-12 must be working toward equilibrium. How do we know that equilibrium can even be attained? What principle of science is this based on?

Apparently, C14 dating was originally developed based on the assumption that C14 and C12 were in equilibrium. It turns out that our atmosphere is 25% OUT of equilibrium. Not only that, but it turns out that nuclear testing alters C14/C12 readings.

I don't see how can we develop any scientific testing method on an equilibrium that doesn't exist and may never exist.

What says we must have equilibrium? What law?

Just like if you put hot water on one side and cold water on the other side and then connect them by a conduit. The water will start to flow toward each other.

That is kind of thing happened to most natural systems. As long as something is changing, that means something is out of equilibrium.

So, if one side of the water is 80°C and the other side is 20°C, what would be the equilibrium temperature? It is not such an easy question, isn't it? It may never happen if something happened to one or both of them.

 

[FallingWaters]

Ah. So, by natural law, things are always moving toward equilibrium.

Yet that doesn't mean they are at equilibrium, or that they will ever achieve it.

 

[sfs]

C-14 will be at equilibrium if the production of C-14 is constant (or changes very slowly compared to the decay rate) and if you wait long enough -- a few half-lives will get you pretty close. The amount approaches equilibrium because the amount that decays is proportional to the amount that is present; the equilibrium value is just the amount of C-14 for which the amount that decays equals the amount that is being produced (which we've assumed to be constant).

In the real world, the rate of production is not constant -- but it also doesn't vary wildly. Since it doesn't vary very much, uncorrected age estimates from C-14 will at least give you a ball-park figure for the age, and you can get a more accurate value by estimating the production rate in the past by comparison with events of known age (mostly overlapping sets of tree rings). The exception to "doesn't vary wildly" is during the era of above-ground nuclear testing, which would give future archeologists fits if they try to date artifacts from the current era.

 

[gluadys]

I don't understand the reason why the C-14/C-12 must be working toward equilibrium. How do we know that equilibrium can even be attained? What principle of science is this based on?

Apparently, C14 dating was originally developed based on the assumption that C14 and C12 were in equilibrium. It turns out that our atmosphere is 25% OUT of equilibrium. Not only that, but it turns out that nuclear testing alters C14/C12 readings.

I don't see how can we develop any scientific testing method on an equilibrium that doesn't exist and may never exist.

What says we must have equilibrium? What law?

Ingore juvenissun. He is apparently confusing radioactive decay with thermodynamics.

I am not sure where you got the term "equilibrium" from in respect to C14 decay. Science is certainly not saying that there is or ever was or ever will be the same amount of c12 and c14 in the atmosphere. C14 is very rare in comparison to c12. Nor does it say that the atmospheric proportions of c12 and c14 are constant. We know for a fact that they are not. As you stated, the proportion of c14 increased due to atmospheric testing of atomic weapons.

So possibly you or your source have been misinformed, or there is still a different meaning to "equilbrium" in this case.

For example, you speak of the atmosphere being 25% out of equilbrium. But was this specifically in reference to c12/c14 ratios? Or was it to carbon dioxide generally? As you know we have been seeing a rapid increase in CO2 levels which has been linked to global warming. Maybe this is the equilibrium being talked about.

Can you give us more specifics on the context in which it is claimed the atmosphere is 25% out of equilibrium? And whether this is really related to c12/c14 ratios or to something else.

 

[FallingWaters]

Ingore juvenissun. He is apparently confusing radioactive decay with thermodynamics.

I am not sure where you got the term "equilibrium" from in respect to C14 decay. Science is certainly not saying that there is or ever was or ever will be the same amount of c12 and c14 in the atmosphere. C14 is very rare in comparison to c12. Nor does it say that the atmospheric proportions of c12 and c14 are constant. We know for a fact that they are not. As you stated, the proportion of c14 increased due to atmospheric testing of atomic weapons.

So possibly you or your source have been misinformed, or there is still a different meaning to "equilibrium" in this case.

For example, you speak of the atmosphere being 25% out of equilibrium. But was this specifically in reference to c12/c14 ratios? Or was it to carbon dioxide generally? As you know we have been seeing a rapid increase in CO2 levels which has been linked to global warming. Maybe this is the equilibrium being talked about.

Can you give us more specifics on the context in which it is claimed the atmosphere is 25% out of equilibrium? And whether this is really related to c12/c14 ratios or to something else.

You're right. I meant the ratios.

 

[gluadys]

You're right. I meant the ratios.

OK, so sfs has kindly explained that "equilibrium" means the rate of c14 decay matches the rate of c14 production.

When the two rates match the proportion of c14 in the atmosphere is constant. Just as the amount in your bank account will be constant if your income matches your expenses.

But, science does not make the claim that decay rates and production rates always match, though they do not tend to vary a lot from each other either.

So we do get varying proportions of c12/c14 in the atmosphere, but not enough to throw dating off by a large margin.

That answer the question?

 

[billwald]

It is an observation, data collected over a period of time, not a law. The primary tool of science is observation.

 

[sfs]

It is an observation, data collected over a period of time, not a law. The primary tool of science is observation.

It is worth noting that the observation was not that the C-14 fraction in the atmosphere was constant, but rather that C-14 dating of objects of known age gave the correct answer. C-14 dating was proposed in the late 40s, and since then the C-14 fraction has been anything but constant, so simply observing the C-14 fraction for a period of time would have been useless. I think it's fair to say that we know that C-14 has been roughly in equilibrium because of inferences from observations, not directly from observation.

 

[juvenissun]

Ingore juvenissun. He is apparently confusing radioactive decay with thermodynamics.

I am not sure where you got the term "equilibrium" from in respect to C14 decay. Science is certainly not saying that there is or ever was or ever will be the same amount of c12 and c14 in the atmosphere. C14 is very rare in comparison to c12. Nor does it say that the atmospheric proportions of c12 and c14 are constant. We know for a fact that they are not. As you stated, the proportion of c14 increased due to atmospheric testing of atomic weapons.

So possibly you or your source have been misinformed, or there is still a different meaning to "equilbrium" in this case.

For example, you speak of the atmosphere being 25% out of equilbrium. But was this specifically in reference to c12/c14 ratios? Or was it to carbon dioxide generally? As you know we have been seeing a rapid increase in CO2 levels which has been linked to global warming. Maybe this is the equilibrium being talked about.

Can you give us more specifics on the context in which it is claimed the atmosphere is 25% out of equilibrium? And whether this is really related to c12/c14 ratios or to something else.

Fallingwaters, this would become your heavy burden if you ignore what I said. This is an illustration on the difference between a professor and a TA.

 

[Mallon]

Fallingwaters, this would become your heavy burden if you ignore what I said. This is an illustration on the difference between a professor and a TA.

In what way was your vague analogy any more sufficient than the detailed explanations given by sfs and gluadys?

I'm still having a really hard time believing you're a professor...

 

[FallingWaters]

OK, so sfs has kindly explained that "equilibrium" means the rate of c14 decay matches the rate of c14 production.

When the two rates match the proportion of c14 in the atmosphere is constant. Just as the amount in your bank account will be constant if your income matches your expenses.

But, science does not make the claim that decay rates and production rates always match, though they do not tend to vary a lot from each other either.

So we do get varying proportions of c12/c14 in the atmosphere, but not enough to throw dating off by a large margin.

That answer the question?

Actually, juvenissun told me what I needed to know. I just needed to know what was driving equilibrium, and his simple but effective analogy reminded me of the answer.

 

[gluadys]

Actually, juvenissun told me what I needed to know. I just needed to know what was driving equilibrium, and his simple but effective analogy reminded me of the answer.

Except it had nothing to do with c12/c14 ratios.

Heat moves to an equilibrium too, when hot and cold contact each other, but its an entirely different process for an entirely different reason.

 

[juvenissun]

Actually, juvenissun told me what I needed to know. I just needed to know what was driving equilibrium, and his simple but effective analogy reminded me of the answer.

Another example is to watch the earth's weather.

The weather conditions on earth will NEVER reach equilibrium (disastrous condition if it did). But the variation is limited within a range. This is an example of dynamic equilibrium on a very large scale.

Any dating system should NOT become any equilibrium state. The system NEEDS to continue to change toward one direction with time.

 

[FallingWaters]

Except it had nothing to do with c12/c14 ratios.
...

Of course you're right.
My question was about the foundational principle driving equilibrium.
The context was C14 dating, but I wanted to understand the law causing equilibrium.


Thank you all for your help.

 

[gluadys]

Of course you're right.
My question was about the foundational principle driving equilibrium.
The context was C14 dating, but I wanted to understand the law causing equilibrium.


Thank you all for your help.

Yes, in general "equilibrium" means "balance". Like balancing the weights on two ends of a teeter-totter till one end is no higher than the other.


Heat will move from its source into the cooler surroundings until the cooler surroundings have warmed up and the temperature is consistently balanced with no "hot" or "cold" spots.

With c14 we can have a balance of production and decay leaving a constant ratio in the atmosphere.

 

[crawfish]

Of course you're right.
My question was about the foundational principle driving equilibrium.
The context was C14 dating, but I wanted to understand the law causing equilibrium.


Thank you all for your help.

I'm glad you're happy now. I'm confused.

 

[Biblewriter]

OK, so sfs has kindly explained that "equilibrium" means the rate of c14 decay matches the rate of c14 production.

When the two rates match the proportion of c14 in the atmosphere is constant. Just as the amount in your bank account will be constant if your income matches your expenses.

But, science does not make the claim that decay rates and production rates always match, though they do not tend to vary a lot from each other either.

So we do get varying proportions of c12/c14 in the atmosphere, but not enough to throw dating off by a large margin.

That answer the question?

This is based upon an unprovable assumption that the production rate of c14 is "more or less constant."

This assumption is based on the fairly well established fact that most c14 is produced by solar radiation, and the reasonable assumption that there have never been any very large variations in the amount of radiation produced by the sun. These facts make the assumption seem reasonable. But this logic neglects a very real possibility.

There is no way to prove that as our solar system moves through space, it has never passed through a cloud or interstellar dust. We know that such clouds exist, and we also know that if they are distant from any star, we cannot see them.

If our planet passed through such a cloud at any time on the past, the production rate of c14 would have been greatly reduced for as long as it took to pass through the cloud. This would have made all objects from that time seem very much older than they really were.

Incidentally, carbon dating and tree ring dating systematically yield results about 10% different at the age limit of tree ring dating, which is ---- wonder of wonders ---- about six thousand years!

 

[Mallon]

There is no way to prove that as our solar system moves through space, it has never passed through a cloud or interstellar dust. We know that such clouds exist, and we also know that if they are distant from any star, we cannot see them.

There's no way to prove that we weren't created by an alien race yesterday with false memories implanted in our brains or that giant purple crickets once roamed the earth (after all, absence of evidence isn't evidence of absence). But if you're going to come up with all these "what if" stories, the onus is on you to demonstrate that they happened, not on us to show you that they didn't.

(All this to say nothing of the fact that carbon dates are generally supported by other independent lines of evidence, like tree rings or ice cores, that could not be explained by the earth's passing through an interstellar dust cloud. Thus, your hypothesis is falsifiable and, in fact, has been falsified.)

 

[Assyrian]

Another example is to watch the earth's weather.

The weather conditions on earth will NEVER reach equilibrium (disastrous condition if it did). But the variation is limited within a range. This is an example of dynamic equilibrium on a very large scale.

Any dating system should NOT become any equilibrium state. The system NEEDS to continue to change toward one direction with time.

Don't forget we are dealing with two distinct systems in carbon dating, one is atmospheric carbon which could quite happily reach equilibrium and not effect carbon dating, the other is the carbon in the sample which stopped taking up atmospheric carbon when it died. From then its carbon does change in one direction.