Radioactivity was first discovered by Madame Curie, and this by accident. She had a photo film lying around near radioactive material and noticed that the material left marks on the film without touching it.
Radioactive radiation is produced by radioactive decay. All substances in the periodic table above lead, which has the ordinal number 82, are radioactive. These substances, such as uranium or plutonium, will eventually break down to lead. Radioactive radiation is divided into alpha, beta and gamma radiation. With alpha radiation, the decaying substance emits a helium nucleus, i.e. 2 protons and 2 neutrons. During beta decay, electrons are released. Ultimately, gamma radiation is nothing more than photons, which the radioactive substance emits. While the alpha and beta radiation in nuclear power plants remain very well shielded by the lead jacket or do not have such a long range themselves, some of the gamma radiation leaves the nuclear power plant even when it is operated properly.
Radioactivity and the absolute theory
The novelty of the absolute theory regarding radioactive radiation is the realization that according to the absolute theory gamma radiation has not only energy but also a mass. This already results from Einstein's equation E = m * c². Correspondingly, functioning power plants leave not only energy but also mass. Gamma rays are nothing more than photons and these have the elemental mass.