ABSTRACT
The physicist Erwin Schrödinger described, back in 1935, one aspect of this strange phenomenon. He placed his cat in a sealed box with a piece of radioactive material which might or might not send out a sub-atomic particle. If it did, the Geiger counter was designed to trigger a release of poisonous gas in the box, and thereby kill his cat. The counter was set up to be triggered just enough to give a 50–50 chance of a particle being detected, and therefore the cat an even chance of being poisoned or not. (In those days, this sort of experiment was acceptable, particularly as it was only a thought experiment.)
