Quantum nanoscience preserve and maximize coherence. Superposition is the quantum phenomena wherein an entity can simultaneously exist in two states. The classic description is the though experiment of Schroedinger’s Cat. In this gedanken experiment, the cat can be both alive and dead until the state of the cat is actually observed. Entanglement can link the quantum states of two or more objects over any distance. Entanglement lies at the heart of quantum teleportation and quantum communication. The pursuit of quantum coherence-enabled functionality includes the enabling fields of quantum nanoscientific research, such as enabling materials and tools that are directed towards the goal
Expectation value (quantum mechanics) to calculate the average momentum, one uses the momentum operator "in configuration space", formula_65. Explicitly, its expectation value is Not all operators in general provide a measureable value. An operator that has a pure real expectation value is called an observable and its value can be directly measured in experiment. The expectation value, in particular as presented in the section "Formalism in quantum mechanics", is covered in most elementary textbooks on quantum mechanics. For a discussion of conceptual aspects, see: Expectation value (quantum mechanics) In quantum mechanics, the expectation value is the probabilistic expected value of the result (measurement) of