Carbon dating

Carbon dating, or carbon-14 dating, is a method for comparing the ages of organic materials such as bones or things made from anything that once lived.

The technique is based on comparing the levels of C-14 and C-12 isotopes in the sample. When the sample was living, the ratio of C-14 to C-12 in the material is the same as in the atmosphere. But after death the C-14 isotope decays into N-14, while C-12 does not. The loss in C-14 is then used to estimate how long ago the sample died, which is typically the same as how long the sample existed.

Current rates of decay of C-14 are such that, if its rate of decay remained constant, then 50% would be list in 5730 years.

Limits of Carbon Dating

First, it is impossible to prove scientifically whether the rate of decay of C-14 has remained constant over hundreds or thousands of years. Some scientists have suggested, based on experimental observations, that the laws of physics do change over time.^{[Citation Needed]}

Second, estimating the age of material using carbon dating assumes that the ratio of C-14 to C-12 was the same in the past as today, which is also impossible to prove scientifically.^{[Citation Needed]}

Due to these fundamental limitations, the only scientific conclusion that can be drawn from carbon dating is that material X is older than material Y when X has lost more C-14 than Y has. It is not possible to determine, with any degree of scientific certainty, how much older X is than Y.^{[Citation Needed]}

Known Errors in Carbon Dating

Even the staunchest advocates of carbon dating admit that it gives errors for material that is younger than 150 years or older than 50,000 years. The errors for material younger than 150 years is ascribed to changes in the ratio of C-14 to C-12 in the atmosphere. The errors for material older than 50,000 years is ascribed to statistical uncertainties inherent in the loss of multiple half-lives.