Can the Sigma Be Removed from the Normalization Equation for a Wavefunction?

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Homework Statement


the wavefunction
Equation: phi(x) = A times the sum over n of 1/(2n+1)^4 times phi_n, where A is a constant and the sum runs over n.


where <
upload_2016-1-30_13-0-34.png
|
upload_2016-1-30_13-1-16.png
> =
upload_2016-1-30_13-0-5.png
. I want to normalize it and find constant normalization A. A is real number.

Homework Equations

The Attempt at a Solution


I know that for normalizing the wave function

Normalization condition written as the integral over all space of psi times psi-star equals 1, with the integral sign and the wavefunction and its complex conjugate shown in plain handwritten-style notation.

but what happen for sigma? can I remove it from equation?
 
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  • Equation: A times the sum over n of 1 divided by (2n + 1)^4, multiplied by phi sub n.
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  • Equation: phi(x) = A times the sum over n of 1 divided by (2n+1)^4 times phi_n, where A is a constant.
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You can't just ignore the sigma! First, can you find an expression for ##||\phi||^2##?
 
I think the equation is :
Handwritten equation: A^2 times the integral of the sum over n of 1/(2n+1)^8 equals 1, with the summation sign and integral sign shown.
because <
upload_2016-1-30_13-0-34-png.png
|
upload_2016-1-30_13-1-16-png.png
> =
upload_2016-1-30_13-0-5-png.png
is it correct? I'm not sure!
but what I do after that?
 
Attachments
  • Handwritten normalization equation: A^2 times the integral of the sum over n and m of 1/((2n+1)^4 (2m+1)^4) equals 1.
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zahra95 said:
I think the equation is :View attachment 95040because <
upload_2016-1-30_13-0-34-png.png
|
upload_2016-1-30_13-1-16-png.png
> =
upload_2016-1-30_13-0-5-png.png
is it correct? I'm not sure!
but what I do after that?

That's obviously not right. If you're stuck with an infinite sum, try a simple sum and see what happens. Try:
##\phi = A(\phi_0 + \frac{\phi_1}{3^4})##
 
Inline equation: the norm of phi equals the square root of the inner product of phi with phi, written as ||phi|| = sqrt(<phi|phi>).
and
Equation: <φ|φ> = A^2 (1 + 1/3^8), written as an inner product of φ with itself.
for n = 0,1
= A^2(1+1/3^8 + 1/5^8 + 1/7^8 + ... )
then it is true that = A^2(1/(2n+1)^8) isn't it?
 
Attachments
  • Equation: double bar of phi equals the inner product of phi with phi, written as ||phi|| = <phi|phi>, with the norm written as a double bar around phi.
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  • Can the Sigma Be Removed from the Normalization Equation for a Wavefunction?
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  • Equation: <φ|φ> = A^2 (1 + 3^8)
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  • Small inline symbol showing the Greek letter phi with a subscript, rendered in math italics.
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  • Equation: <φ|φ> = A^2 (1 + 1/3^8 + ...), a series of reciprocal eighth powers of odd integers multiplied by A squared.
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Was that integral sign in post #3 a typo?

For the next bit, trying googling "sums of reciprocal powers".
 
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