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I am having a bit of difficulty wading through the what seems to be multiple usages for Observables in Quantum Mechanics.
" Mathematically observables are postulated to be Hermitian operators.. " However it seems as if the observables are actually the eigenvalues of the operator: Operator Postulate as well as, according to wikipedia "a system observable is a measurable operator, or gauge, where the property of the system state can be determined by some sequence of physical operations" Wikipedia Observable. But here is a prime example of where they are calling the operator $O$ an observable, but as it "operates" on some vector and there are eigenvectors and eigenvalues (the observables), associated, I don't understand why they are using observables for the operator as well Operator as Observable. I can see that observables are associated to operators, but I don't see why they are called observables.
Any help is appreciated.