Because I am a nuclear chemist, there are certain things I don’t want to believe. For example, I don’t want to believe quantum mechanics is wrong just because it is incompatible with general relativity. ....
For a long time, there was something else I didn’t want to believe. I didn’t want to believe that the half-lives of radioactive isotopes could change. It seemed so clear to me at the time: radioactive half-lives depend on the energetics of the nucleus, and the energy levels in the nucleus are (roughly speaking) about 100,000 times that of the electrons in an atom. Thus, if nature exposes a radioactive atom to stress, the electrons should be the ones that deal with the stress, not the nucleus. The nucleus is under the electron cloud, and it deals in energies that are so much greater than electron energies, that the electrons effectively “shield” the nucleus from being affected by most of the stress that nature can throw at it.
Over the years, however, the data have drug me (kicking and screaming the entire way) to the point where I have to admit that radioactive half-lives can change, and in some cases, they can change quite substantially.
For example, Otto Reifenschweiler showed that when tritium (a radioactive form of hydrogen) was incorporated into small particles of titanium and heated, the radioactivity of the tritium decreased by 40%1. This means the half-life of the radioactive decay increased. F. Raiola and his collaborators saw a roughly 6 percent decreased half-life for a radioactive form of polonium when it is layered in copper metal. 2. Interestingly enough, Raiola’s paper references another study that I am waiting on from interlibrary loan in which the same form of radioactive polonium had a 300% shorter half-life when it is layered in palladium.
Nuclear chemists and physicists have no coherent model to account for these changes in radioactive half-life. However, that is not unusual. It often takes generations for theorists to actually explain why experimentalists see what they have seen. Also, the explanation is not nearly as important to me as the fact that it clearly can happen, even though all my education (through graduate school) said that such a thing is clearly impossible.
In fact, it seems that what was considered impossible just 20 years ago is being demonstrated all over the place. Indeed, there is now clear and convincing evidence that the rate of radioactive decay varies (slightly, but still measurably) based on the distance between the earth and the sun! 3 Interestingly enough, two independent labs have been seeing this effect since the early 1980s, but both were too afraid to publish the results, thinking they were making some systematic error. Instead, the error is clearly in the assumption that radioactive half-lives are constant.