How to prove uniqueness solution of the 3D wave

In summary, the conversation is about the three-dimensional wave equation and how to prove the uniqueness of its solution. Boundary conditions and initial conditions are discussed, as well as the need for specifying the given conditions. The importance of initial conditions for obtaining a unique solution is also mentioned.
  • #1
lotusquantum
9
0

Homework Statement



The three dimensional wave equation:
[itex]c∂^{2}u/∂t^2 = ∇^2 u[/itex]

boundary conditions :
[itex]u(x,y,z,t) = F(x,y,z,t)[/itex] on S

initial conditions:
[itex]u(x,y,z,0) = G(x,y,z)[/itex]

[itex]∂u/∂t(x,y,z,0)=H(x,y,z)[/itex]

Homework Equations


how to prove the uniqueness solution of the above equation?

The Attempt at a Solution


Please recommend me some methods or examples to prove such problems. thansk
 
Last edited:
Physics news on Phys.org
  • #2
boundary conditions :
u(x,y,z,t)=F(x,y,z,t)
For all x,y,z,t? If F is a given boundary condition, the unique solution u=F is trivial. If F is something else, or that condition is true for some x,y,z,t only, please specify this.

Assuming u and u' are both solutions, what about u-u'?
 
  • #3
sorry! It's u(x,y,z,t) = F(x,y,z,t) on S
 
  • #4
Where is S?

The initial conditions should be sufficient to get a unique solution.
 

1. How do you define uniqueness in the context of 3D wave solutions?

Uniqueness in the context of 3D wave solutions refers to the property of a solution being the only possible solution to a given problem. In other words, there is only one solution that satisfies all the given conditions and is consistent with the laws of physics.

2. What is the significance of proving uniqueness in the 3D wave equation?

Proving uniqueness in the 3D wave equation is crucial because it ensures that the solution is reliable and accurate. It also helps to validate the mathematical model and provides a better understanding of the physical phenomenon being studied.

3. What are the common methods used to prove uniqueness in the 3D wave equation?

The most common methods used to prove uniqueness in the 3D wave equation are the energy method, the maximum principle, and the method of descent. These methods involve manipulating the equations and using mathematical techniques to show that there is only one possible solution.

4. Is it always possible to prove uniqueness in the 3D wave equation?

No, it is not always possible to prove uniqueness in the 3D wave equation. In some cases, there may be multiple solutions that satisfy the given conditions and are consistent with the laws of physics. This is known as non-uniqueness, and it can occur when the problem is not well-posed or when there are multiple physical phenomena interacting with each other.

5. How does proving uniqueness in the 3D wave equation impact real-world applications?

Proving uniqueness in the 3D wave equation has a significant impact on real-world applications. It ensures that the results obtained from mathematical models are accurate and reliable, which is crucial in fields such as engineering, geophysics, and acoustics. It also provides a better understanding of the behavior of waves in different physical systems, which can help in developing more efficient and effective solutions.

Similar threads

  • Calculus and Beyond Homework Help
Replies
2
Views
271
  • Calculus and Beyond Homework Help
Replies
2
Views
324
  • Calculus and Beyond Homework Help
Replies
1
Views
705
  • Calculus and Beyond Homework Help
Replies
7
Views
798
  • Calculus and Beyond Homework Help
Replies
7
Views
688
  • Calculus and Beyond Homework Help
Replies
13
Views
1K
  • Calculus and Beyond Homework Help
Replies
8
Views
470
  • Calculus and Beyond Homework Help
Replies
3
Views
1K
  • Calculus and Beyond Homework Help
Replies
7
Views
555
  • Calculus and Beyond Homework Help
Replies
6
Views
390
Back
Top