Amongst some of the commonest isotopes on Earth, such as carbon-11, nitrogen-13 and oxygen-15, we find the notorious carbon-14 isotope. However, while all the previously mentioned isotopes have half-lives ranging from a few tens of minutes to few seconds, carbon-14 decays much slower having a half-life of about 5730 years. Why this is happening remains mostly a mystery, but researchers from Stony Brook University, led by Gerald Brown, propose a brand new model which could result in a better understanding of the strong nuclear forces that keep the atomic nucleus from falling apart.

Carbon-14 radioactive isotope represent an invaluable tool for archaeologists, who routinely use it to determine the age of organic material. Once a living organism ceases to exist, it would immediately stop ingesting carbon-14 isotope. Archaeologists can date organic remnants by determining the ratio between carbon-14 isotopes and nitrogen-14, as carbon-14 decays into the latter through radioactive emissions.

In the early 1990's Brown proposed, for the first time, a mechanism that would enable carbon-14 isotopes to experience such a high half-life time. Radioactive decay inside an atom is determined by nucleus instability. Because protons and neutrons are kept together inside the nucleus by mesons carrying two types of strong nuclear forces, Brown suggested that each of the other short lived radioactive isotope experience differences in the strength between the two, which immediately results in a nuclear instability that allows some sub-atomic particles to escape the atom.

On the other hand, the carbon-14 isotope should have a smaller difference between its strong nuclear forces, which may be why it has a much longer half-life time. Ultimately, the difference would grow bigger until the isotope decays into the nitrogen-14 isotope.

Now, Brown and Jeremy Holt propose a series of calculations that could verify their eighteen year old theory. The findings have been detailed in the next issue of Physical Review Letters. The same study also give credit to a series of predictions made in the middle of the 1950s by Igal Talmi which established for the first time a connection between the high half-life of the carbon-14 isotope and the tensor force of the nucleus. On the other hand, Brown's mathematical model is partially incomplete, as it only includes certain types of meson interactions, but could easily be extended to cover all the interactions inside the nucleus.