Associated Legendre functions and orthogonality

In summary, the conversation discusses the orthogonality property of the associated Legendre function and the derivative of the associated Legendre function. The conversation explores the possibility of an orthogonality property for the derivative and the sum of the functions. The speaker has searched for this property in various textbooks but has not found any information.
  • #1
soikez
5
0
According to the orthogonality property of the associated Legendre function

[tex]P_l^{|m|}(cos\theta)[/tex]

we have that:

[tex]\int_{0}^{\pi}P_{l}^{|m|}(cos\theta){\cdot}P_{l'}^{|m'|}(cos\theta)sin{\theta}d\theta=\frac{2(l+m)!}{(2l+1)(l-m)!}{\delta}_{ll'}[/tex]

What I am looking for is an orthogonality property for the derivative of the associated Legendre function

[tex]P^{'}_{l}^{|m|}(cos\theta)[/tex]:

something like that perhaps:

[tex]\int_{0}^{\pi}P^{'}_{l}^{|m|}(cos\theta){\cdot}P^{'}_{l'}^{|m'|}(cos\theta)sin{\theta}d\theta=?[/tex]

or even taking into consideration the fact that the derivative of the associated Legendre function is:

[tex]P^{'}_{l}^{|m|}(cos\theta)=\frac{lcos{\theta}P_{l}^{|m|}(cos\theta)-(l+m)P_{l-1}^{|m|}(cos\theta)}{sin\theta}[/tex]

after some manipulations on my equation an orthogonality property over the sum below:

[tex]\sum_{l}^{\infty}\sum_{m=-l}^{m=l}cos{\theta}P_{l}^{|m|}(cos\theta)-(l+m)P_{l-1}^{|m|}(cos\theta)e^{jm\phi}[/tex]

Thanks in advance
 
Physics news on Phys.org
  • #2
I am looking for a similar thing. I have looked in all the spherical harmonics textbooks I can find, but have had no luck. I will let you know if I have anything.
 

1. What are Associated Legendre Functions and why are they important in mathematics?

Associated Legendre functions are a type of special function in mathematics that are used to solve problems involving spherical harmonics. They are important because they have many applications in physics, engineering, and other scientific fields.

2. How are Associated Legendre Functions related to Legendre Polynomials?

Associated Legendre functions are a generalization of Legendre polynomials, which are a type of orthogonal polynomial. They are used to solve problems involving spherical coordinates, while Legendre polynomials are used for problems in Cartesian coordinates.

3. What is the orthogonality property of Associated Legendre Functions?

The orthogonality property of Associated Legendre functions states that the integral of the product of two different functions with different orders and degrees is equal to zero. This property is useful in solving problems involving spherical harmonics and in proving the completeness of the functions.

4. How are Associated Legendre Functions used in quantum mechanics?

In quantum mechanics, Associated Legendre functions are used to solve the Schrödinger equation for particles in a spherically symmetric potential. They are also used to determine the probability distribution of particles in a three-dimensional space.

5. Are there any real-world applications of Associated Legendre Functions?

Yes, there are many real-world applications of Associated Legendre functions. They are used in geodesy to model the Earth's gravitational field, in electromagnetism to describe the radiation pattern of antennas, and in fluid dynamics to study the flow of fluids in spherical coordinates, among others.

Similar threads

  • Calculus
Replies
29
Views
719
Replies
3
Views
1K
Replies
2
Views
292
Replies
4
Views
352
  • Calculus
Replies
3
Views
789
Replies
16
Views
1K
Replies
7
Views
1K
  • Calculus
Replies
15
Views
3K
Replies
16
Views
1K
  • Introductory Physics Homework Help
Replies
20
Views
1K
Back
Top