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DiracRules
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Too few examples to explain "The principles of quantum mechanics" by dirac.
Hi!
I studied my first course of quantum physics without a technical formalism (I'm studying physics engineering).
I find some hindrances in paragraph 20.
It says (I'm translating from Italian):
What I cannot understand is how to transpose these symbols in effective calculations.
For example, if [itex]|P>[/itex] represent the superposition of the first two states of a particle (say an electron) in an infinite well, what is [itex]\psi(\xi)[/itex]? How can I find it?
Hi!
I studied my first course of quantum physics without a technical formalism (I'm studying physics engineering).
I find some hindrances in paragraph 20.
It says (I'm translating from Italian):
After a few lines, he says that we can formally write [itex]|P>=\psi(\xi)[/itex], where [itex]\psi(\xi)[/itex] is the wave function.In a representation in which the complete set of commuting observables [itex]\xi_1',\ldots,\xi_u'[/itex] are diagonal any ket [itex]|P>[/itex] will have a representative [itex]<\xi_1'\,\,\xi_u'|P>[/itex] or [itex]<\xi'|P>[/itex] for brevity. This representative is a definite function of the variables [itex]\xi'[/itex], say [itex]\psi(\xi')[/itex]. The function [itex]\psi[/itex] then determines the ket [itex]|P>[/itex] completely, so it may be used to label this ket, to replace the arbitrary label [itex]P[/itex]. In symbols, if [itex]<\xi'|P>=\psi(\xi')[/itex] we put [itex]|P>=|\psi(\xi)>[/itex]
What I cannot understand is how to transpose these symbols in effective calculations.
For example, if [itex]|P>[/itex] represent the superposition of the first two states of a particle (say an electron) in an infinite well, what is [itex]\psi(\xi)[/itex]? How can I find it?