Posted by jlwile on September 1, 2010
One of the foundational assumptions of the various radioactive dating techniques that attempt to measure the age of things is that the half-life of a radioactive isotope does not change significantly over the time period being measured. Even though we have been measuring half-lives for only about 100 years, those who want to believe that the earth is billions of years old are forced to assume that over those billions of years, the half-lives of various radioactive isotopes have not changed significantly. As I have pointed out before, this is a terrible extrapolation, and a careful scientist should avoid using it unless there are very good reasons to believe it is justified. As more and more data come in, it becomes more and more clear that there are very good reasons to believe it is not justified.
I previously discussed data that indicate radioactive half-lives are not constant, but over the past year and a half, some new information has come out that lends more strength to the claim. As I discussed previously, two independent labs noticed that the decay rate of certain isotopes were influenced by the distance between the earth and the sun. They produced a paper in 2008 reporting on their findings: the rate at which these isotopes decayed varied in perfect sequence with the changing of the distance between the earth and the sun1 Many in the scientific community blamed this on experimental errors such as environmental changes or problems with the detectors that were monitoring the isotopes. Studies published over the past year and a half, however, seem to have ruled out these possibilities and have lent even more credence to the idea that the sun influences radioactive decay rates.
The scientists have ruled out factors such as temperature, atmospheric pressure, and humidity as causing the observed effects2, and they have also shown it is not the result of changes in background radiation.3 As a result, it looks like the original data are not the result of experimental error. The detected variation in radioactive decay is, most likely, a real effect.
In addition to this, the same investigators have shown that the radioactive decay of magnesium-54 decreased during the solar flare of December 13, 2009.4 Indeed, as the solar flare caused a monitor detector to register high levels of protons and X-rays coming from the sun, the detectors monitoring the radioactive decay of magnesium-54 showed a distinct reduction in rate. In addition, another “blip” of increased protons and X-rays coming from the sun four days later coincided with another decrease in the rate of the decay of magnesium-54.
So there seems to be a real interaction between the sun and the rate at which certain radioactive isotopes decay. Since these are relatively new results, not a lot of extra investigation has been done, so we don’t know how widespread this interaction is. It could be between the sun and all radioactive isotopes, or it could be between the sun and just a few radioactive isotopes.
Now don’t get all excited. These results are measureable, but they are small. If you are looking for something that shows “billions of years” worth of radioactive decay could occur in a few thousand years, these results will not please you. The observed effect is simply too small to affect radioactive dating techniques in any significant way. There is evidence that what appears to be “hundreds of millions of years” of radioactive decay can occur very quickly, but as you might expect, that evidence is indirect. The experiments I am discussing here are direct evidence that at least some radioactive half-lives can change at least somewhat.
While these studies don’t directly affect the validity of radioactive dating techniques, they nevertheless tell us something very important: We clearly do not understand the process of radioactive decay as well as some would have you believe. Until the original study was published, no one would have believed that the earth-sun distance had anything to do with the rate of radioactive decay here on earth. Even after the study was published, many refused to believe it, blaming environmental issues or detector problems. Now that the follow-up studies produce even more evidence for the reality of the effect, nuclear scientists still have no real idea of what could possibly be causing it. Sure, there are some guesses being bandied about, but none of them make sense given what we know about radioactive decay.
So what’s my point? It’s quite simple. We have only been studying radioactivity for about 100 years. In order to believe radioactive dating techniques that tell us the earth is billions of years old, you have to assume that radioactive half-lives have stayed constant for billions of years. “Don’t worry,” old-earth scientists have assured us, “we KNOW that radioactive decay rates cannot fluctuate based on any natural processes, so there is no reason to doubt the results of these radioactive dating techniques.”
Well…now we KNOW that at least one natural process (something having to do with the sun) does affect radioactive decay rates. What we don’t know is the extent or possible magnitude of the process. We also don’t know what other surprises lie in store for us when it comes to radioactive decay. The extrapolation involved in radioactive dating techniques can only be justified if we KNOW that radioactive half-lives cannot change significantly as a result of natural processes. Since these data make it clear that we DON’T KNOW the extent to which natural processes can cause changes to radioactive half-lives, it is obvious that the extrapolation is simply not justified.
2. Javorsek II, et. al., “Power spectrum analyses of nuclear decay rates,” Astroparticle Physics, 34:173-178, 2010.
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3. Jere H. Jenkins, et. al., “Analysis of environmental influences in nuclear half-life measurements exhibiting time-dependent decay rates,” Nuclear Instruments and Methods in Physics Research A, 620:332-342, 2010.
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4. Jenkins, J.H. and E. Fischbach, “Perturbation of nuclear decay rates during the solar flare of 2006 December 13,” Astroparticle Physics, 31:407-411, 2009.
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