Schrödinger's cat is a thought experiment, sometimes described as a paradox, devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects, resulting in a contradiction with common sense. The scenario presents a cat that might be alive or dead, depending on an earlier random event.

Massive stars go supernova when iron is fused. Iron is the final and heaviest element in the fusion process in stars. The core becomes heavy and cannot contract any more, the core collapses, rebounds of the surface and the star explodes as a type II supernova.

The Morrígan ("phantom queen") or Mórrígan ("great queen"), also written as Morrígu or in the plural as Morrígna, and spelt Morríghan or Mór-ríoghain in Modern Irish, is a figure from Irish mythology who appears to have been considered a goddess, although she is not explicitly referred to as such in the texts.

The Morrígan is a goddess of battle, strife, and sovereignty. She sometimes appears in the form of a crow, flying above the warriors, and in the Ulster cycle she also takes the forms of an eel, a wolf and a cow.