Help Solve for the normalization constant of this QM integral

In summary, the conversation discusses finding the normalization constant for a given wavefunction. However, the integral required to calculate the normalization constant does not converge, indicating that the given wavefunction is not normalizable and therefore not a valid wavefunction. The person also questions whether it could be a typo in the given wavefunction, suggesting a different expression that would make more sense from a quantum mechanical perspective.
  • #1
casparov
29
6
Misplaced Homework Thread
Homework Statement
find A
Relevant Equations
psi = A exp [ - x^2 / (2+ix) ]
I'm given the wavefunction

ψ = A exp(-x^2/(2 + i x))


and I need to find the normalization constant A.

I believe that means to solve the integral

1/A^2 = integral_(-∞)^∞ e^(-x^2/(2 + i x)) e^(-x^2/(2 - i x)) dx


The question does give some standard results for the Gaussian function, also multiplied by x to some different powers in the integrand, but I can't seem to get it into that form.
Whatever I do, I get an x in the denominator of the exponent, and makes it impossible to solve for me.
 
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  • #2
casparov said:
I'm given the wavefunction

View attachment 326989

and I need to find the normalization constant A.

I believe that means to solve the integral

View attachment 326990
That is correct. However, this integral does not converge, so the given wave function is not normalizable (hence not a valid wave function).
 
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  • #3
DrClaude said:
That is correct. However, this integral does not converge, so the given wave function is not normalizable (hence not a valid wave function).
Sorry for the misplacement, it was a question on a final exam. Seems super odd to give this when the follow up questions implied it was normalizable. Thank you very much. Contacted my professor
 
  • #4
casparov said:
Sorry for the misplacement, it was a question on a final exam. Seems super odd to give this when the follow up questions implied it was normalizable. Thank you very much. Contacted my professor
Could it be a typo?
$$
\psi = A \exp \left(- \frac{x^2}{2} + i x \right)
$$
would make more sense from a quantum mechanical point of view.
 
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1. What is the normalization constant in quantum mechanics?

The normalization constant in quantum mechanics is a mathematical factor that is used to ensure that the total probability of finding a particle in any state is equal to 1. This is necessary because in quantum mechanics, the wave function of a particle describes the probability of finding the particle in a particular state, rather than its exact position or momentum.

2. Why is it important to solve for the normalization constant?

Solving for the normalization constant is important because it allows us to accurately calculate the probabilities of different states in quantum mechanics. Without a properly normalized wave function, the probabilities would not add up to 1, which would violate the fundamental principles of quantum mechanics.

3. How is the normalization constant calculated?

The normalization constant is calculated by integrating the square of the wave function over all possible values of the particle's position or momentum. This integral is set equal to 1 and solved for the normalization constant.

4. What are the units of the normalization constant?

The units of the normalization constant depend on the units of the wave function. For example, if the wave function is in units of meters^-1/2, then the normalization constant would have units of meters^-1/2.

5. Are there any shortcuts for solving for the normalization constant?

Yes, there are some shortcuts that can be used to solve for the normalization constant in certain cases. For example, if the wave function is a Gaussian function, the normalization constant can be calculated using the standard deviation of the function. Additionally, in some cases, the normalization constant may be known or can be determined from physical constraints, eliminating the need for a full calculation.

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