is: used to refer to the condition of a system. Its exact meaning varies according to circumstance, but it generally implies a sufficiently detailed account of the condition of a system to distinguish it from any other condition that would behave differently in the circumstances under discussion. The nature of the required account is indicated by an appropriate qualifier as in mechanical state, thermodynamic state, quantum state, bound state, equilibrium state, stationary state, etc.
is specified: in classical physics by the values of various observable physical quantities (e.g. pressure, volume and temperature for an equilibrium state of a fixed quantity of ideal gas).
is specified: in quantum mechanics by a wavefunction that determines the probability that measurements of observables will yield specified eigenvalues of the operator corresponding to the observable.
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