I’m sure my readers are aware of Schrödinger’s cat.
For those who are not, it is a “thought experiment” by the extraordinarily clever Edwin Schrödinger designed to analyse and explain (!) aspects of quantum mechanics and quantum superposition.
Wikipedia provides a helpful explanation as below.
Schrödinger’s cat: a cat, a flask of poison, and a radioactive source are placed in a sealed box. If an internal monitor detects radioactivity (i.e. a single atom decaying), the flask is shattered, releasing the poison that kills the cat.