Gaussian units

The Gaussian system of units, also called Gaussian CGS system or natural system of units is a physical unit system based on the CGS system and this adds to electromagnetic units. The Gaussian system of units takes the Coulomb force law as a starting point for the definition of electromagnetic parameters and not, as the SI system, the Ampère force law for two parallel current-carrying conductor. It should be noted here clearly that the difference between the Gaussian and the SI system is not merely a question of units, but are the sizes in the two systems differently introduced and therefore also measured in other units. Strictly speaking, in the two systems of concepts thus to different size systems.

In today's practice, the Gaussian unit system, in particular the units is rarely used in pure culture, and Statvolt Statcoulomb be used any more. Far more often a mixture of Gaussian and units of the MKS system is used in which the field strength is approximately expressed in volts per centimeter.

In theoretical physics, the Gaussian system of units is often preferred over the MKSA system because it electric and magnetic field obtained identical units, which is more logical, because these fields are just different components of the electromagnetic Feldstärketensors. You go through Lorentz transformation produced apart, so are just different " forms " of electromagnetism in general, and in principle separable phenomena. Further immersed in the formulation of the Maxwell equations for the velocity of light as a factor, which is useful in relativistic considerations.

For some applications to be Gaussian units, such as the magnetic field strength measured in Gauss, compared with the corresponding SI - units is preferred because the number of values ​​are then easier to handle. For example, the earth's magnetic field of the order of 1 Gauss.

Transformation formulas

The following are the formulas for the transformation of the conceptual system of Gauss given ( without star ) formula are listed in the SI system ( with star ). It can be seen that this is not just a simple change of units.

• Gaussian system:
• SI system:

In addition, in the SI system two field constants - the electric and the magnetic field constant - necessary, which does not exist in the Gaussian system.

Apply the relationships

This results, inter alia, the conversion formulas for material sizes electric polarization and magnetization

And slightly different forms of the Maxwell equations.