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Topic: normalization Constant & Eigenvalue  (Read 7495 times)

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Offline love48

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normalization Constant & Eigenvalue
« on: January 30, 2011, 11:59:54 AM »
*The wave function Ψ(theta), for the motion of a particle in a ring is  Ψ= Ne^(imφ).
Determine the normalization constant.

*a)  Find the values of the constant "a" that makes exp(-ax^2) an eigenfucntion oof the operator d^2/dx^2 - bx^2 where B is constant. What is corresponding eigenvalue?
   b) show that the function f(x) = x exp (-ax^2) is an eigenfunction of the operator in part a) if the constant "a" is properly chosen, find its eigenvalue:
these function are basic to the quantum mechanical theory of vibrating systems.

« Last Edit: January 30, 2011, 12:10:13 PM by love48 »

Offline love48

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Re: normalization factor
« Reply #1 on: January 30, 2011, 12:01:31 PM »
for the first one, i never learned normalization factor and i don't get what the second question for eigenfunction is trying to ask. I know how to to do eigenfunction and find its value but i don't what this one is asking for.


Offline tamim83

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Re: normalization Constant & Eigenvalue
« Reply #2 on: January 30, 2011, 04:50:40 PM »
A "normalized" function satisfies,



You need to integrate over all space (from to ) or within the boundary conditions for the problem.  I think for this though you need to use the boundary conditions for particle on a ring.  

So, to normalize the function, you need to find a value of N that satisfies the normalization condition.  

Note: To get the complex conjugate ( ), replace all "i' with "-i".  
« Last Edit: January 31, 2011, 08:01:41 AM by tamim83 »

Offline love48

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Re: normalization Constant & Eigenvalue
« Reply #3 on: January 30, 2011, 06:36:34 PM »
I can't see the image you posted. I use Google Chrome

Offline tamim83

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Re: normalization Constant & Eigenvalue
« Reply #4 on: January 31, 2011, 08:01:12 AM »
Quote
I can't see the image you posted. I use Google Chrome

Ok.  The normalization condition is that the integral over all space for the wavefunction multiplied by its complex conjugate is equal to one.  Like I said, since your problem has boundary conditions, you need to integrate over those instead of "all space".  Does that help some?  

Offline love48

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Re: normalization Constant & Eigenvalue
« Reply #5 on: January 31, 2011, 02:52:33 PM »
yes got the answer :-)
N = 1/ Squre root of 2pie
:)
do you know the other one?

Offline love48

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Re: normalization Constant & Eigenvalue
« Reply #6 on: January 31, 2011, 02:53:01 PM »
Thank you :) ;D ;D

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