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A quantity represented by a theory and connected to a possible measurement outcome or statistical distribution.
The mathematical representation of an observable depends on the theory: functions on phase space in classical mechanics and self-adjoint operators or POVMs in quantum theory.
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This is an authored directed relation from the source endpoint to the target endpoint.
An observable is a physical quantity represented so that the theory assigns possible outcomes or expectation values.
A more specific theory, model, entity class, or regime is obtained by restricting or extending the scope of a broader framework.
wp-physics-observablenlab-physics-observablewp-physics-physical_quantitynist-codataThis is an authored directed relation from the source endpoint to the target endpoint.
A state determines or constrains the probability distribution of observables represented by the theory.
The target represents a state, property, observable, or state-dependent description associated with the source system or theory.
nist-quantum-theorywp-physics-observablenlab-physics-observablewp-physics-physical_statenlab-physics-stateEach relation below starts at this concept.
This is an authored directed relation from the source endpoint to the target endpoint.
A quantum observable is the quantum-theoretic specialization of the general observable concept.
A more specific theory, model, entity class, or regime is obtained by restricting or extending the scope of a broader framework.
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