Ive been thinking about this for a while, what is the exact mechanism for radioactivity that results in there being a half life. Say you have a single radioactive isotope of Uranium, this particle would ultimately emit an alpha particle or some other form of radiation and thereby quickly returning to a stable element. However this does not happen, we have huge half lives for uranium which I presumed was because when densely packed enough, the radiation emmited by one would then increase another and therefore it would take a long time for it to spread to the outside. But if this were the case, we could just spread out nuclear material over a very large surface area and reduce its half life significantly. But this is incorrect by what ive heard that you can't reduce or change half lives. can anyone fill me in on what im missing?