# Speed of a soliton and its energy

1. Apr 1, 2009

### somasimple

Hi All,

A one dimensional soliton will have the mathematical form $f(x - ct)$ where c is the speed of propagation and f represents some envelope function.
If we suppose that c1 is a speed and c2 another one where c2>c1.

If E1 is the energy needed to maintain the speed and shape of the soliton.

What happens when the speed change from c1 to c2?
1/ if the shape is constant?
2/ if the shape is reduced?
3/ Is the energy needed enlarged/augmented?