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An observable represented in standard quantum mechanics by a self-adjoint operator, or more generally by a positive-operator-valued measure for a measurement.
Incompatible observables need not have simultaneously sharp values because their operators do not commute.
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This is an authored directed relation from the source endpoint to the target endpoint.
Operator-algebraic quantum theory organizes bounded observables in -algebras.
A mathematical concept supplies part of the formal language, state space, representation, or analytic machinery used by a scientific or mathematical-physics concept. The source is the mathematical predecessor; this does not claim that physical content follows from mathematics alone.
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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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Quantum mechanics represents observables by operators or generalized measurements.
The target represents a state, property, observable, or state-dependent description associated with the source system or theory.
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Sharp quantum observables are represented by self-adjoint operators or their spectral measures.
A mathematical concept supplies part of the formal language, state space, representation, or analytic machinery used by a scientific or mathematical-physics concept. The source is the mathematical predecessor; this does not claim that physical content follows from mathematics alone.
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The spectral theorem supplies the projection-valued measure and functional calculus of a self-adjoint observable.
A mathematical concept supplies part of the formal language, state space, representation, or analytic machinery used by a scientific or mathematical-physics concept. The source is the mathematical predecessor; this does not claim that physical content follows from mathematics alone.
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An expectation value is evaluated for a specified observable in a specified state.
The source supplies a substantive formal ingredient, dynamical sector, law, field content, or mechanism of the target theoretical framework.
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