Question about which "branch" of physics this would be... I posted this in General since I wasn't sure... and it's not an actual problem, per se, just an inquiry about the fields of physics... (sorry if this is the wrong forum >_>) During work at lunch one day, I was stumbling through wikipedia articles and found myself reading about nuclear power plants, reactor cores, and how they are powered through the fusion of uranium and plutonium. As a mechanical engineer, this was all very interesting to me, even though I don't know much about the "fusion" of said materials - but I'd like to learn. I began clicking on things like nuclear decay, and radioactivity, half life, etc etc.... My question is - what kind of book or source can I buy/go to that would be a good "starter" guide for understanding radioactivity and related topics like this? Radioactive energy and such. Thanks guys!!