Electromagnetism

Appendix 4

Some Key Players in Electromagnetism and Special Relativity

Special relativity can be considered as one of the first contributions to the theory of general relativity, developed at the beginning of the 20th century. These theories are intended to explain classical mechanics and its paradoxes, as well as electromagnetic interactions. The theory of general relativity takes into account the phenomenon of gravity/acceleration.

The foundations of the special relativity theory are derived from Newton’s theory of universal gravity and Maxwell’s theory of electromagnetic interactions, discovered a few years earlier. In his theory, Maxwell revealed the existence of electromagnetic waves. The light waves are also rightly suspected to be electromagnetic waves. Now, these equations reflect the fact that the velocity of an electromagnetic wave is not different as a function of the inertial coordinate system.

This statement can be better understood with the following metaphor. A car at 100 km/h is doubled at night by a car at 130 km/h. The headlights of both vehicles are on. An observer stands on the road opposite and sees the two cars coming at him/her. Now, the observer sees the light from the headlights arriving at the same speed, close to 300,000 km/s. This is even if the cars were traveling at a speed close to that of the light.

There is still a fairly active controversy today over the authorship of special relativity. Some scientists support Einstein, others Poincaré, and ...