Quantum Mechanics: Finding wavefunction in momentum space.

In summary, the conversation is about solving a problem involving finding the wave function in momentum space and calculating the expected values of <p> and <p^2>. However, when attempting to calculate <p>, it results in an infinite value. After reviewing the work, it is discovered that an error was made when completing the square. The issue is resolved and the individual is reminded to take a break and get some rest.
  • #1
Xyius
508
4
Basically, the problem gives me a wave function and asks me to find the wave function in momentum space. It then asks me to find the expected value. Namely <p> and <p^2>. The problem is, when I try to calculate <p> it blows up to infinity. What am I doing wrong? Here is my work...
http://imageshack.us/a/img805/1449/qmhw1.jpg
 
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  • #2
Check the step where you complete the square...I think you may have made an error at that point.
 
  • #3
Of course! Thank you very much. I guess that is a sign I should stop doing work and sleep. :]
 

1. What is the wavefunction in momentum space?

The wavefunction in momentum space is a mathematical representation of a quantum system that describes the probability of a particle having a certain momentum. It is related to the wavefunction in position space through a mathematical transformation known as the Fourier transform.

2. How is the wavefunction in momentum space determined?

The wavefunction in momentum space can be determined using the Schrödinger equation, which is a fundamental equation in quantum mechanics that describes how the wavefunction changes over time. It can also be calculated using the Fourier transform of the wavefunction in position space.

3. What is the significance of finding the wavefunction in momentum space?

Finding the wavefunction in momentum space allows us to determine the momentum of a quantum system, which is a crucial quantity in understanding the behavior of particles at the quantum level. It also helps us to calculate other important physical quantities, such as the kinetic energy and momentum uncertainty of a particle.

4. Can the wavefunction in momentum space be visualized?

Unlike the wavefunction in position space, which can be visualized as a probability distribution in three-dimensional space, the wavefunction in momentum space is a complex mathematical function and cannot be directly visualized. However, its properties and behavior can be studied and analyzed using mathematical techniques.

5. How does the wavefunction in momentum space relate to the uncertainty principle?

The wavefunction in momentum space is related to the uncertainty principle, which states that the more precisely we know the momentum of a particle, the less precisely we can know its position, and vice versa. This is because the Fourier transform of the wavefunction in position space is used to calculate the wavefunction in momentum space, and the two representations are related by the uncertainty principle.

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