Operators and Complete State Descriptions in Quantum Mechanics

black_kitty
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What for do we need operators in QM. Where is the complete state description of a quantum object?
 
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You don't *need* operators--for example, Feynman's path integral approach to quantum mechanics only uses regular old numbers (no operators)... Of course, you may not like path integrals any better than operators since they are not really well-defined mathematically.
 
black_kitty said:
What for do we need operators in QM. Where is the complete state description of a quantum object?

P.A.M. Dirac, “The Principles of Quantum Mechanics”, 4-th edition, Oxford, (1958).

The Hilbert spaces are perfectly defined mathematical structures.

Regards, Dany.
 

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