What is the Uniqueness principle ?

[Julian18]

Hi, there
Sorry for this simple question, I just a newbie in EM, Could anyone gives me some explicit explainations about what is uniqueness principle? and how to apply it in practice.

TIA.

 

[Julian18]

Uniqueness principle

?

 

[Wiley]

Re: Uniqueness principle

The uniqueness principle says, that for given geometry and initial conditions, there is one and only one solution to Maxwell's equations.

How does one apply it in practice? Well, one doesn't. At least not directly. It does not help you solve the problem; however, if you can find a solution, you know it's the solution.

It does allow us to do comparisons, e.g., simulation vs. measurements. It also allows us to bicker endlessly about who is better: CST or HFSS. Because both should be converging to the same solution.

 

[Jone]

Re: Uniqueness principle

First of all, uniqueness theorems are in general very powerful; quite obviously, without the theorems one could never find a unique solution.

The uniqness principle is also of importance in image problems. In the common textbook example, one wants to find the E-field of a point charge held above a ground plane. A much simpler and equivalent problem (applies only for the region above the ground problem) is to remove the ground plane and insert a charge at the opposite position to the the old charge, that is, mirror the geometry but remove the ground plane. This problem still satisfies the same equations and boundary values so the uniqueness theorem says that it also must have the same solution. Without this theorem, we wouldn't belive this were the solution since we solved a different problem.

 

[A.Anand Srinivasan]

Re: Uniqueness principle

the uniqueness principle states that a solution ( derived or at random) if it satisfies the boundary condition of the given system then it is the one and only unique solution.....