The Coming of the Quantum Cats can - given different social conditions - develop completely different character traits (timid or assertive, benevolent or predatory, etc.) The title refers to the famous thought-experiment known as "Schrödinger's Cat", where the outcome of a real-world event depends on a quantum event. By some interpretations, the real-world object, in this case a cat, must be in two states simultaneously until it is observed. However, the story is more closely related to the many-worlds interpretation of quantum mechanics where all possible outcomes of an event occur, each in its own parallel universe. The same concept was treated, somewhat more pessimistically, in
Expectation value (quantum mechanics) A particularly simple case arises when formula_1 is a projection, and thus has only the eigenvalues 0 and 1. This physically corresponds to a "yes-no" type of experiment. In this case, the expectation value is the probability that the experiment results in "1", and it can be computed as (3) formula_24. In quantum theory, also operators with non-discrete spectrum are in use, such as the position operator formula_25 in quantum mechanics. This operator does not have eigenvalues, but has a completely continuous spectrum. In this case, the vector formula_11 can be written as a complex-valued function formula_27 on the spectrum