SOME WORDS ABOUT STRUCTURE VOID’s GEIGER COUNTER DEVICE
Geiger counter device measures what we call radioactive disintegrations. Natural radioactivity is everywhere, not only near from nuclear power plants. Radioactive atoms & molecules naturally tends to disintegrate, and to release some particules which can be detected with a Geiger counter device.
Because there is no model able to know when a disintegration will occur, we often use this phenomenon as a pure random source. If we measure the time between two disintegrations, because it varies totally randomly from a disintegration to the next one, we can generate random numbers.
Read more about randomness there: