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It is accepted by many scientists, teachers, students, the media, and the average well-informed modern person, that billions of years ago our universe came into being by rapidly expanding and cooling, and some blob of matter congealed into our Earth, that millions of years ago life appeared and evolved, carbon dating accuracy debate man hundreds of thousands of years ago, and that there is a great deal of incontrovertible scientific evidence to back this up.
So much I have gathered in bits and pieces from books, lectures, TV shows, and casual conversations. Now, all else being equal, I would accept these things on their good authority. But when it comes to the origin of the universe, the Earth, and life, I face a predicament. I am a Christian, and as such I believe that the Bible is the Word of God, written by men but inspired by the Holy Spirit, and therefore true and infallible.
My own rough count puts the age of the Earth around 6, years. Crediting the Word of God above the word of man, thousands of Christians, including many Ph. However, disregarding such a thorough and widely-accepted view of cosmic history is not a step to be taken lightly.
The Biblical worldview itself carbon dating accuracy debate that God gave man the ability to learn about Him and His creation through observation and reason; therefore science should be a valid way of learning about our world—and a variety of scientific disciplines, from geology to biology to astronomy, yield a fairly cohesive picture of the ancient earth. Many Christians, from some of my own family and teachers to the famous author C. Lewis, reconcile the discrepancy by reinterpreting key passages of Scripture in a less literal sense 2.
After all, the Bible was not intended to be a scientific textbook; certain parts of it are clearly not meant to be read in the most literal sense; and Christians, like everyone else, are all too prone to misinterpreting our own doctrine. Is it really impossible to take Genesis at face value without discounting scientific inquiry? And can a creationist perspective offer a satisfactory, intellectually honest alternative? These are questions I must answer before I can rest satisfied in either position.
That is, no one is without bias. Old-earth Christians and secularists assume the world is old and see evidence that the world is old, while creationists assume the world is young and see evidence that the world is young.
A full-fledged defense of either position is well beyond the scope of this paper; but as a case in point, let us consider one tool science has given us, and examine how definitive, carbon dating accuracy debate proof is much harder to come by than we tend to imagine. As a creationist, I had always supposed that if carbon dating contradicts the Bible, carbon dating must be wrong, or based on faulty assumptions. But such an off-hand dismissal does not do credit to my position if I do not even know how carbon dating works.
Here, I look into the technique of carbon dating, the assumptions that must be made in order to use it for dating objects, and the measure of uncertainty in its. Can the raw data provided by carbon dating be reconciled to Biblical creation if viewed with Biblical assumptions?
If not, what does that mean for the creationist perspective? The measurement of radioactive carbon as a dating technique was first proposed by Libby, Anderson, and Arnold.
The basic idea is as follows. This 14C enters the global carbon cycle, dissolved in the oceans as carbonate and bicarbonate ions, and also taken in by plants as carbon dioxide and thence consumed by animals 4. So, every living thing acquires some amount of 14C mixed in with its normal 12C—roughly grams of 14C for every gram of 12C.
But whenever a living thing dies, it is removed from the carbon cycle—its 14C is no longer replenished, and decays away 5. Since its discovery by Becquerel inradioactive decay has been thoroughly studied and is well-characterized. The amount of a radioactive material is known to decrease exponentially with time. This type of decay is defined by a half-life, the amount of time required for some amount of radioactive material to decay to half that amount.
The half-life of 14C is about 5, years, meaning that if we have a gram lump of 14C now, in 5, years we would have a lump with 5 grams 14C and 5 grams 14N 6. This well-known decay pattern makes it possible to calculate, given a present amount of 14C, how much 14C there was at any point in the past. Libby and co-workers proposed that by measuring carbon dating accuracy debate current amount of 14C in a once-living object, and estimating the amount of 14C in it when it died, one could calculate, to within a few hundred years, how long ago that object died or was removed from the global carbon cycle.
This, of course, requires accurate measures of the current and original 14C content. But this can be difficult in practice, as the amount of 14C, and therefore, detectable radiation, is very low. Libby describes a method in which a sample to be dated is first processed to isolate the carbon and convert it into a convenient chemical form, then this refined carbon sample is placed in a sophisticated radiation detection device 7.
Carbon dating accuracy debate recently, 14C content is also measured by atomic mass spectroscopy, which separates atoms by mass 14C being heavier than 12Cand it is possible to date samples with less than 0. But knowing the current carbon content is not enough.
It carbon dating accuracy debate also necessary to know the amount of carbon present when the subject died or was removed from the carbon cycle. Since this happened a long time in the past, there is no way to measure it, and it must be estimated with a series of assumptions and approximations.
In their first paper on carbon dating, Libby, et al. They then used this average value as the original 14C content, assuming that the worldwide 14C distribution was the same in ancient times as today. But this assumption is not quite correct:. This means that the radiocarbon clock can race ahead or seemingly stop for up to 5 centuries. As a result, raw radiocarbon dates sometimes diverge from real calendar years by hundreds or even thousands of years.
Thus researchers must calibrate the clock to for these fluctuations, and that can be a challenge. International calibration curves have been developed for this purpose, based on fossilized trees and marine deposits.
Tree-ring data is used for up to about 12, years ago, and marine data beyond that. It is believed that such calibration methods can be extended to 50, years before present Beyond that, too little 14C would remain to be detected—after all, 50, years is about nine 14C half-lives, so no more than 0.
Aside from the estimation of and adjustment for ancient atmospheric 14C fluctuations, other assumptions must be made for carbon dating to be useful. First, one must assume that 14C decay is truly exponential, with a constant half-life.
This is not in doubt, as radioactivity is well-understood, but since we cannot observe 14C decay over periods comparable to its half-life, it should be kept in mind. Even the value of the 14C half-life is subject to some uncertainty, with measured values ranging from 5, to 6, years. The former is not strictly true, but attempts have been made to correct for this with calibrations, as discussed. The latter is more troubling.
After thousands to tens of thousands of years, a sample is bound to experience changes to its carbon content.
There is also the possibility of carbon atoms in the sample being exchanged with others in the environment, the possibility of contaminating samples during pretreatment, and countless other potential problems to consider on a case-by-case basis. Last, it is necessary to assume that radiocarbon is, and has been, uniformly distributed among air, water, plants, and animals over the whole world, so that anything dying at a given time will have the same 14C content as any other thing dying at that time.
Libby, et al. While it would be possible to characterize the distribution of 14C in present times, it is impossible to be certain what it was like thousands of years ago. In the end, the only way to verify the accuracy of carbon dating is to use it to date objects of known age, and compare the radiocarbon date with the actual date.
Arnold and Libby did just this with samples of wood obtained from archaeological sites and dated by archaeological and historical evidence, or in some cases carbon dating accuracy debate tree rings. The ages of their samples ranged from 1, to 5, years, and their radiocarbon dates agreed well—all but one within one standard deviation of the known age the standard deviations were on the order of a few hundred years.
Libby later reported difficulty in obtaining older historical samples:.
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We had thought initially that we would be able to get samples all along the curve, back to 30, years before the present; we would put the points in, and then our work would be finished. You read statements to the effect that such and such a society or archeological site is 20, years old. We learned rather abruptly that these s, these ancient ages, are not known accurately; in fact, the earliest historical date that has been established with any real certainty is about the time of carbon dating accuracy debate 1st Dynasty in Egypt.
Another early study by Flint and Deevey compared radiocarbon dates to dates determined by geologic stratigraphy location in rock layersreaching back to 20, years.
More recently, studies have focused not on checking radiocarbon dates against known samples, but on using samples of known age to improve the calibration curves discussed above While such calibrations allow carbon dates to be reconciled with and improved by other dating techniques, they rely upon the assumption that all the techniques involved are trustworthy; it is difficult, if not impossible, to verify any method one against an objective, absolute date.
Of course, there have also been documented failures of radiocarbon dating. Bird, et al.
There are several cases where parts of living or recently-deceased animals were carbon-dated to several thousand years ago, usually because the organisms had access to old, marine carbon sources Also, many samples that other methods date to be hundreds of thousands to millions of years old — so that they should have no detectable 14C — such as fossil fuels and diamonds, have been found to contain 14C, implying that they are less than 50, years old So far, I have described carbon dating and some of the theory, measurements, and ideas that underlie it.
Within the scientific community at large, it carbon dating accuracy debate to be considered a well-established and reliable dating method, though subject to assumptions and sources of error, as is any indirect measurement. There is little doubt that we understand the physics of carbon decay, can observe the present carbon cycle, and can measure accurately the amount of carbon in a sample; and even hard-core creationists do not argue with this empirical evidence But the fundamental necessity of making certain assumptions about the ancient earth may leave room for reinterpretations of the raw data.
First, it should be noted that carbon dating cannot be used to prove that the Earth is millions of years old. As mentioned above, carbon dating is limited to carbon dating accuracy debate 50, years, as the radiation becomes too weak to measure with practicality. There are radiometric techniques that, in theory, can be used to date things millions of years old, by using much longer-lived radioactive species, such as uranium These methods also have implications for creationists, but a discussion of them is beyond the scope of this paper.
It is critical in carbon dating to know the amount of 14C present at the time of death. As discussed above, this is calculated by assuming that the amount of 14C in the atmosphere has been constant for tens of thousands of years, with corrections made based on ancient tree rings and marine sediments. Implicit in this is the idea that the overall rates of 14C production and disintegration are equal, so that the total amount stays more or less the same. Carbon dating accuracy debate this is reasonable if the Earth has been exposed to cosmic radiation for a long period of time.
But from a creationist perspective, the Earth is young enough a little older than one half-life of 14C that such a steady-state should not yet have been established, so that the rate of 14C formation in the atmosphere should exceed its overall rate of decay This is perhaps the strongest alternative explanation young-earth scientist have to offer at present, and there has been some evidence that it is the case If this is the case, ancient atmospheric 14C levels would be lower than predicted, making all samples appear to be older than they are in reality.