Anyone who is currently involved in undergraduate work in physics should take the following post with a large grain of salt, it steps outside of the boundaries of currently accepted theory... Radioactive decay, is attributed to the weak nuclear force (the electro-weak force). Once our understanding of the weak nuclear force evolved to to include an electromagnetic component, it does not seem reasonable to me, to assume that just because stable isotopes do not decay through electro-weak interaction(s), that electro-weak interaction(s) do not have any affect on stable isotopes. The questions are: Can electro-weak interactions affect electron transitions in stable isotopes? If so, can a solar event and/or variations in the the earth/sun distance, that affect the decay rate of unstable isotopes, have an influence, either directly or indirectly, on the electron transitions in a stable isotope? And.., if the conditions above do affect electron transitions in stable isotopes, is there a measurable difference in that effect, when measured on earth as opposed to in an orbit around the earth? Should electro-weak interactions, be found to influence electron transitions and vary under the influence of solar activity and distance, it could represent a serious challenge to the application of the Lorentz transformations, to length contraction and time dilation of an object in motion, as well as requiring some remodeling of general relativity. This would not affect the use of the Lorentz transformation as applied to observations made from frames of reference in relative motion to one another, only to their application to objects in motion. If what is suggested above were to be confirmed, it could lead to significant re-evaluations of both quantum theory and general relativity. It also has some potential to resolve one of the conflicts between the two.., the definition and nature of space itself.