Is the Displacement Operator Tψ(x)=ψ(x+a) Hermitian?

Rude
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Consider the displacement operator Tψ(x)=ψ(x+a). Is T Hermitian?
 
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To get you started, what's the definition of a Hermitian operator?
 
here is the definition: <f│Ag>=<Af│g> always if A is Hermition.
Don't know how to start.
 
Rude said:
here is the definition: <f│Ag>=<Af│g> always if A is Hermition.

Suppose the wave function of the state |g> is ##\psi_g(x)## and the wave function of state |f> is ##\psi_f(x)##. Then what does the above definition of an operator A being Hermitian say if you translate the inner product into an integral of wave functions, using

##\langle a | b \rangle = \int dx \psi_a(x)^* \psi_b(x)##

and plug in A = T?
 
Is this what you are suggesting?

<f│Tg>=∫dxΨ(x)*ψ(x+a)

If so I don't know how to proceed.

It does not look like this would give <Tf│g> but don't know why.
 
Rude said:
Is this what you are suggesting?

<f│Tg>=∫dxΨ(x)*ψ(x+a)

Yup.

Rude said:
It does not look like this would give <Tf│g> but don't know why.

If you think they aren't equal, perhaps you can find an explicit counterexample?
 
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