Science Forums 2

[Roberto]

There must be a little mistake when you say that the definition of the speed of light is extracted from the definitions of meter and second. In fact, nowadays, the definition of the second, as I told you in my last post, makes reference to the frequency of the light emitted by the cesium atom in some specified transition, there is not circular about that because you can just detecty the photon emittef in the process and use its frequency to define the second.

After that, the meter is defined by means of the distance that light can travel in certain fraction of second. Not a circular definition again. Both definitions are made with reference to basic processes in nature.

Physicists do not prefer any system of units, they simply use the one that is more convenient in each case, since hte reference system is not something fundamental. The importance of a unit system comes from padronization of language and measurements and is much more important in engineering and experimental physics, for example, than in theoretical physics.

If you propose a new system of units you only need to show applications where it is more convenient than the others at use. COncerning the definition of units, I think people is happy with those they have because they make reference to basic measurable processes.

That´s only my opinion.