mercredi 14 juin 2017

Assumptions involved in Carbon dating


Bill Ludlow


See that "National Center for Science Education" thing?

Status in group
I'm seeing a pattern in this group with the use of the word "assumptions." Whenever a creationist here can't explain something in accordance with their worldview they toss out that word as a kind of safety net or end all comment.

Radiometric dating? "Assumptions"

Sedimentary layers form in different environments? "Assumptions"

Millions of years? "Assumptions"

Transitional species? "Assumptions"

If you expect to be taken seriously by anyone with a scientific background you had better be prepared to list those assumptions and answer why the assumptions are invalid, otherwise you will be seen as someone who just brushes off solid evidence by repeating a catch phrase and hand waving. Sometimes what people call "assumptions" are actually inferences based on logical deductions. An assumption is an implicit or unstated premise. Assumptions don't stand on their own. When combined with facts, valid assumptions lead to valid inferences.

[Skipping image, for now.]

Skipping
some, down to my answer:

Hans-Georg Lundahl
Radiometric dating? "Assumptions"
_______________________
With C14, once you date anything to 40 000 BP, you cannot calibrate that against historical texts dated historically to 40 000 year ago, you need to assume that the carbon 14 level throughout atmosphere and living things was much the same as it is today.

If it was in fact more like 1.5 percent of what it is today, you get instead ... that it took less than 5730 years to get from 1.5 percent to the 0.792 percent modern carbon we date as 40 000 BP.

The point is : some evolutionists think this is not an assumption at all, but a basical natural fact, that other evening i was hearing some guy call the carbon 14 level in the atmosphere and in still living things "a constant" which it is not.

NEXT question is which assumption is best warranted : a) constancy of carbon 14 level in atmosphere? or : b) reliability of the biblical chronology?

The first of these has as a consequence unreliability of biblical chronology and therefore of Bible as history.

The second of these has a consequence that carbon 14 level has risen (and that drastically, by faster additions than the ones we see now, since we are already in an equilibrial state in atmosphere).

So, to a normal, unbiassed philosopher, the discussion goes : which consequence is most unacceptable? or : which assumption is best warranted?

To one such who is agnostic, there is a really good test : first ears of cultivated wheat found 19 000 BP, first systematic trace of what about 10 000 BP. Right, man cultivated some ears of wheat for fun, didn't find it tasty, went back to hunting and gathering, and ten thousand years later only started going farmer?

Or the carbon chronology is messed up due to rising carbon levels? In that case there may have been a few generations or a century or two between oldest ancient wheat and second oldest wheat we have today. This sounds reasonable.

"Un administrateur
a désactivé les commentaires pour cette publication."

[No more comments possible on this status! It was an admin who did it.]

BUT before this happened, Bill Ludlow had given some answers, and so has Ken Hansen, which I will need to adress on blog:

Bill Ludlow
Scientific Laws backed by mathematical calculations are not assumptions, sorry.

Radioactive decay and exponential laws
By Ian Garbett
https://plus.maths.org/content/radioactive-decay-and-exponential-laws


Answered here
There is no scientific law which states that the carbon 14 level in atmosphere needs to remain all eternity around 100 percent modern carbon [or pmc for short].

That is the ONE divergence between me and conventional carbon dating, and it involves NO divergence about what radioactive decay nor of what exponential laws of mathematics are.

In fact, it very totally builds on them.

You see, suppose the level were rising from 90 pmc to 100 pmc. The beginning of the period of rise would have only* 870 extra years, the end of it none. So, the period is only lengthened by 870 years.

Suppose instead we were looking at the rise from 20 to 30 pmc.

Beginning the period we get the extra years* at 13 300 and ending it we get 9950

13300
09950
03350

The period is now lengthened by 3350 years. More than half of a halflife, not just 870 years.

If instead we were looking at the change from 10 to 20 pmc, we get a doubling. Can you guess what the period will be lengthened by?

I would say a halflife.

Shall we test?

Beginning the period, we have* 19050 extra years and ending it we have 13300 of them.

19050
13300
05750

5750 is not far from the expected 5730. So the period is lengthened by a halflife. So is the period going from 5 to 10 or from 2.5 to 5 pmc : 24750 to 19050 gets a 5700 years lengthening, 30500 to 24750 is lengthened by 5750.

24750
19050
05700

30500
24750
05750

Due to the exponential laws precisely, at the beginning of a rise of carbon 14 levels - and no natural law cited as such precludes this - the small changes (compared to at present) of carbon 14 levels will give big lengthenings of time scales.

Also, due to exponentiality working same fashion of decay at same times whatever value one starts with, the extra years at the beginning - what would be detected as the age by scientists getting back in a time machine and dating recently felled trees or recently fallen twigs - remains an extra to whatever age supervenes in real years with lower carbon levels in object due to decay rather than due to timing in a theoretically possible carbon 14 rise.

* In all examples I am using the same "carbon 14 dating calculator" which I have used so often before and which is put online by evolutionists :

https://www.math.upenn.edu/~deturck/m170/c14/carbdate.html

Your turn now : you test for the rise from 1.25 to 2.5 pmc. Try to guess how much the period will be lengthened? You have fewer extra years at the end and you subtract these from the more extra years at the beginning.

Ken Hansen
The ratio of C-14 to C-12 in the atmosphere's carbon dioxide molecules is about 1.3×10-12, and this value is ASSUMED constant for the main part of archaeological history since the formation of the earth's atmosphere.

Bill Ludlow
"since the formation of the earth's atmosphere."

Nope, only for about the last 55,000 years since that is all the method is good for using standard counting techniques, and there are known fluctuations figured in. How far off would the assumptions have to be to make something that dates to 50,000 years fit into the YEC timeline?

Answered here
I have been working on that exact question for more than a year, since 2015 in october/november.

I have placed now the year of the Flood (2957 BC according to St Jerome and 3358 BC according to Syncellus) at carbon dated 40 000 BC. This means that sth dating 40 000 BP has 35026 extra years according to St Jerome.

2017
2957
4974

40000
04974
35026

35026 extra years means the carbon level was at 1.445 pmc. Which is about 69 times lower than the assumed c. 100 pmc.

Let's suppose the level was rising in the years between Creation and Flood too, this means the limit is this thing being dated to 5199 BC, but that is very unrealistic, we will still deal with it as a limit here:

2017
5199
7216

50000
07216
42784 extra years

42784 extra years = a carbon level of 0.565 pmc, or c. 177 times lower carbon 14 level in atmosphere than expected by evolutionist assumptions.

Ken Hansen
That is an excerpt from the article you linked

Bill Ludlow
Okay, well "archaeological history" only goes back 2.5 million years with the discovery of the first tools, but we still are only talking about the atmospheric conditions within the last 55,000 years.

Answered here
Actually, the 2.5 million years are by a totally different dating method, namely mainly by K-Ar (potassium 40 to argon 40, reliability depends on there being no excess argon, which apparently sometimes there is, as said by evolutionists themselves about K-Ar datings of Mount St Helens)

We cannot say as per datings whether a K-Ar dated object from "2.5 million years ago" is less or more recent than a carbon dated one from "50 000 BP"

Ken Hansen
If C14 started being produced 6000 years ago, it would make a huge difference in the age calculations. From what I've read, the rate of decay and the rate of production of C14 is still out of equilibrium. This fits in with 6000 years but not 55000.

Bill Ludlow
Why?

How could we possibly date something at 40,000 years if the rate of decay only fits a 6,000 year old earth?

Answered here
Ken, you are wrong, if the equilibrium were not already reached, we could not get a consistent half life for otherwise very well attested and very consistent last 2500 years.

Bill, you are wrong because you think we are talkuing about a different rate of decay, we are talking about a different level of initial C14.

Neither of you could probably have guessed that the buildup in order to fit an equilibrium reached 2500 years ago needs to involve an initially way faster production of C14 than now. One of my tables gave 20 times as fast as now, this means that the cosmic radiation would have been 20 times as great (supposing proportionality is direct and a "linear graph" between levels of the two).

A cosmic radiation 20 times higher in the year of the Flood as to now sounds much, but it is still not very much higher than the present total background radiation at Princeton. It's like going from 6 to 8 milliSieverts per year or less.

Ken Hansen
Because the rates should equalize within 30000 years

If there was little or no C14 6000 years ago, it would look pretty old if equilibrium is assumed.

Bill Ludlow
What evidence do you have there was no C 14 6000 years ago?

More assumptions?

Ken Hansen
Yep. You have yours, I have mine.

Answered here
Here I must agree with Ken : we are differing from Bill on what assumptions are MOST reasonable and what consequences of an assumption are LEAST acceptable.

The problem is, Bill and his fellows have been taught as if their case did not even need untested and untestable assumptions. It does.

Other problem, there seems to be some recent conspiracy around to "read" or "understand" creationists arguing about this, as if they were arguing about the rate of radioactive decay. Some few are, most of us are arguing about some kind of buildup of carbon 14 levels in the atmosphere. And this is being constantly ignored, despite this explanation having been around for decades, since Henry Morris, since Edgar Andrews and it has been restated recently by Kent Hovind as well.

I have a hard time seeing how intelligent atheists (and other evolutionists whom I consider syncretistic with the religious system called atheism, most times the word is used) could so systematically miss this without conspiring in some way to ignore the obvious.

If Bill Ludlow had taken the time to actually read what I wrote (the first thing I wrote, marked Hans-Georg Lundahl, not the rest marked "Answered here"), he would have known I was not challenging the exponential mathematics, I was not challenging the decay rate of C14 either, because I was instead challenging something else. Namely stability of carbon 14 level.

Then Ken Hansen brings it up again:

"The ratio of C-14 to C-12 in the atmosphere's carbon dioxide molecules is about 1.3×10-12, and this value is ASSUMED constant for the main part of archaeological history since the formation of the earth's atmosphere."

And Bill Ludlow again gasses on, after a few takes about

"How could we possibly date something at 40,000 years if THE RATE OF DECAY only fits a 6,000 year old earth?"

I don't think he is generally retarded, I think he is acting on this particular matter!

Signing my answers and for quotes from Bill and Ken being by copy-paste:

Hans Georg Lundahl
Nanterre UL
St Basil's inthronisation
as bishop of Neo-Caesaraea
14.VI.2017




It seems I misunderstood him, he was blocking me. I tested on the other profile I have./HGL

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