- #1
Aziza
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According to Griffiths QM book, after he derived the stationary state solutions to the Schrodinger equation for a particle in an infinite potential well, which are just functions of sine, he claims that these stationary solutions are orthogonal and complete.
I agree that they are orthogonal (since sin(nx) and sin(mx) are orthogonal for n!=m), but I definitely disagree that they are complete (meaning that ANY function f(x), odd or even, can be written in terms of these stationary states). For example, you definatelly cannot write f(x)=cos(x) using only a basis of sine functions.
Is there something I am missing here?
Thanks!
I agree that they are orthogonal (since sin(nx) and sin(mx) are orthogonal for n!=m), but I definitely disagree that they are complete (meaning that ANY function f(x), odd or even, can be written in terms of these stationary states). For example, you definatelly cannot write f(x)=cos(x) using only a basis of sine functions.
Is there something I am missing here?
Thanks!
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