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The Special Theory of Relativity

STRWe mentioned in a previous chapter that in 1905 A. Einstein published three works. The third one was about Electrodynamics of moving particles and it meant to change scientists' way they conceived nature.

Einstein's thesis begins with a known experiment: A moving magnet in a solenoid results current. Reversely, a motionless magnet in a moving solenoid creates current again. Einstein was motivated to make this experiment having in his mind the concept of the Ether. After a while he said: "All the laws that are in effect in Electrodynamics and Optics must affect the same way all frames of reference, were laws of Mechanics are in use".

Modern physics accepts that no body and no effect cannot have a speed greater than that of light in space:

c=299.792.458 m/s

and it is independent from the frame of reference we use.

Even though this speed appears to us inconceivable, what makes it extraordinary is the fact that it is finite. This makes an interstellar travel practically impossible. The speed of light could help us reach a planet of our solar system soon, but to travel to Alpha Centauri would take us years. What is important here is the fact that no scientist could prove the existence of a greater speed and at the same time neither could measure c, until nowadays.

Einstein's doubts

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