What Is a Postulate in Quantum Mechanics?

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The discussion centers on the concept of postulates in physical theories, which are foundational assumptions that underpin the predictions of the theory. Postulates, such as the constancy of the speed of light and the equivalence of gravitational and inertial mass, are assumed rather than derived and can be tested for correctness. The importance of an axiomatic structure in theories, particularly in nonrelativistic quantum mechanics, is highlighted, with emphasis on its six axioms and their various formulations. Different formulations, such as those by Dirac, von Neumann, and Feynman, illustrate the flexibility in expressing the same postulate, particularly regarding time evolution. Overall, the discussion emphasizes the critical role of postulates in shaping the framework of physical theories.
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If some one could explain the concept it would be most apreciated.
 
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It is something that is assumed at the "beginning" of a theory. The remainder of the theory's predictions are conclusions derived from its postulates. Postulates can be tested for correctness, but they are assumed, not derived.

Some examples of postulates:

The speed of light is constant for all observers.
Gravitational and inertial mass are the same.

- Warren
 
Each physical theory should be endowed with an axiomatical structure.From my reading and understanding experience,the best of them all is the one of (Nonrelativistic) Quantum Mechanics.Each if its 6 axioms has more fomulations (wording and mathematical expressions) depending upon the formulation of the theory:Dirac's (a.k.a.traditional),von Neumann's,Feynman's,...
There's one postulate (the IV-th,i.e.the time evolution postulate) which,in every formulation aforementioned,can be expressed in 3 different ways,depending upon the picture one adopts:Schrödinger,Heisenberg or interaction (a.k.a.Dirac-Tomonaga-Schwinger).And then of course you have the representations:occupation number,occupation number-energy,position,momentum.Then of course you have the original formalism of matrix mechanics and wave mechanics,but this is not really a part of the axiomatical structure,as one finds them as particular realizations of the various ways of describing the concept of "physical state".

Daniel.
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks
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