Can the Inverse Spectral Problem Determine W(x) from Known Eigenvalues?

  • Thread starter zetafunction
  • Start date
  • Tags
    Inverse
Another option is to use numerical techniques to solve the inverse spectral problem, but this also requires some assumptions and approximations. In summary, the inverse spectral problem is a complex and challenging task, and the specific approach for obtaining W(x) will depend on the details of your problem.
  • #1
zetafunction
391
0
could someone give me some info about inverse spectral proble ??

my doubt is the following, let us suppose we know the spectrum or more precisely the value of the function/distribution

[tex] Z(u)= \sum _{n} Cos( u \lambda _n) [/tex] is known for u >0 , so i can calculate Z(u) exactly for every positive u

my next assumption is that this set of eigenvalues (lambda) belongs to the self-adjoint operator

[tex] -D^2y(x) + W(x)y(x) [/tex]

my problem is that i do not know what W(x) is , is ther using the inverse spectral theory a method to obtain a differential , integral or other kind of equation for W(x) ??

another possible question , let us suppose that [tex] -D^2y(x) + W(x)y(x) [/tex] is a 1-D Scrodinger equation associated to a scattering problem, then how could i recover W(x) ? , if possible give me analytic (approximate) solutions please, thank you very much.
 
Physics news on Phys.org
  • #2
The inverse spectral problem is a difficult one, and the answer to your questions will depend on the specific details of your problem. Generally speaking, the inverse spectral problem involves finding a differential or integral equation whose spectrum (or the value of the function/distribution Z(u)) is known. In other words, given a set of eigenvalues, one can attempt to find the associated differential or integral equation. However, this is not always possible, as there may be multiple equations with the same set of eigenvalues. In the case of a 1-D Schrödinger equation with a scattering problem, the inverse spectral problem becomes even more difficult. The most common approach is to solve an inverse scattering problem, which involves using the measured scattering data to infer the potential W(x). This can be done by using methods such as the Marchenko equation or the Gel'fand-Levitan equation. However, these methods are not always exact and can only provide approximate solutions for W(x).
 

FAQ: Can the Inverse Spectral Problem Determine W(x) from Known Eigenvalues?

What is the inverse spectral problem?

The inverse spectral problem is a mathematical problem in which the goal is to determine the properties of a system based on its spectral data. This involves finding the potential or coefficients of a differential equation that produces a given set of eigenvalues and eigenfunctions.

What is the difference between the direct and inverse spectral problem?

The direct spectral problem involves finding the eigenvalues and eigenfunctions of a given system, while the inverse spectral problem involves determining the properties of a system based on its spectral data.

What is the significance of the inverse spectral problem?

The inverse spectral problem has applications in various fields such as quantum mechanics, fluid dynamics, and signal processing. It allows us to understand the behavior and characteristics of complex systems based on their spectral data.

What are some approaches to solving the inverse spectral problem?

Some common approaches to solving the inverse spectral problem include the Gel'fand-Levitan-Marchenko equation, the inverse scattering transform, and the factorization method. These methods involve using the spectral data to reconstruct the potential or coefficients of the system.

What are the challenges in solving the inverse spectral problem?

The inverse spectral problem can be challenging due to the non-uniqueness of solutions, the limited amount of spectral data available, and the ill-posed nature of the problem. It also requires advanced mathematical techniques and computational methods to solve complex systems.

Similar threads

Back
Top