Can anyone explain why?
Depends on the nature of your function to begin with.. more detail needed.. probably due to orthogonality condition
What is [itex] <q| [/itex],an eigenstate of the momentum operator,or of the position operator (actually of their adjoints,but,because they are selfadjoint,you can think that way as well)?
If it's for the momentum operator,then [tex] |p> [/itex] is an eigenstate as well,and the normalization condition reads:
[tex] <q|p> =2\pi\hbar \delta(q-p) [/tex]
,but if it's for the coordinate operator,then the scalar product is zero,since one of them is an eigenvector from a Hilbert space and the other is a linear functional over another Hilbert space.
So,anyway,what u've written there is wrong.
sorry I meant <x|p>=exp(ip.x)
and I think I have it
It's a long time since I did QM, and I started reading Prof Zee's Quantum field theory in a nut shell. He quotes this very early on without proof and I couldn't see where it came from. Thanks for comments.
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