Radioactivity was first discovered by Madame Curie, and that by chance. She had a photographic film lying around in the vicinity of radioactive material and noted that the material left behind without touching tracks on this film.
Radiation is ie. produced by radioactive decay. Radioactive materials are all that stand in the periodic table of ahead of plumb, which has the atomic number 82. These substances, such as uranium or plutonium decay, eventually to plumb. Radioactive radiation is divided into alpha, beta and gamma radiation. The alpha radiation emitted by the decaying substance has a helium core that is 2 protons and 2 neutrons. With beta-decay electrons are released. Gamma radiation is ultimately nothing other than photons, that are emitted by the radioactive material. While nuclear power plants remain in the alpha-and beta-radiation from the plumb sheath very well shielded, and have even less wide range, even with proper operation leaves a part of the gamma-radiation, the nuclear power plant.
Radioactivity and the absolute theory
The novelty of the absolute theory of radiation is about the realization that after the mass conservation law gamma-radiation is not only energy but also has a mass. This follows already from Einstein's equation E = m * c ². Accordingly, it also leaves a functioning power plants not only energy but also mass. Gamma rays are photons and nothing else and these have the elementary mass.