At the age of 25, Albert Einstein(1879-1955)has come up with his Theory of Relativity, actually, the theory of Special relativity. This was at the year of 1905.

Ten years latter, at the year of 1916, after lots of mental effort did he published his theory of General Relativity.

Both theories did make a huge change in the perception of Energy, Matter, and Space. The Special relativity deals with bodies and particles moving in a uniform, constant velocity relative to each other, while the General Relativity deals with accelerated bodies.

We will discuss here the Special relativity only, and will leave the General relativity for another article.

Well, what are the basics behind the Special Relativity?

Actually Einstein used already known facts, or partially known facts, and known idea and concepts, and embedded them into a single complete theory, and reached innovative ideas.

As a matter of fact, Einstein used the known idea that light speed is constant, no matter what the frame of measurement is, as long as we deal with non-accelerated systems. Using this constraint in already known Lorenz transformation formulas eventually ended up with the some great innovations. One of them is that we no longer discuss a three dimensional space and a uniform constant Time domain. Actually we now have a four-dimensional Space-Time domain, in which Time is one of the dimensions, and is no longer uniform nor absolute. It can “flow” faster or slower (known as Time Dilation). Similarly, the three classical dimensions of space now flexible and can “stretch” or “shrink” (known as Length Contraction).

The “new” characteristics of the space-time domain depend on the relative velocity of bodies and particles, and the velocity of the observers, relative to each other. Note that this does not have an impact as long as velocities are of the daily use order. Such phenomenon do occur only when velocities reach tens percentages of the light velocity. The Special relativity equations show that bodies that move/travel with velocities that are near light velocity, will move slower, and will “shrink” in length, for an observer positioned on earth.

Another outcome of the Specific relativity is that Matter and Energy being equivalent. This means that matter can transform to energy, and vice versa. This idea is expressed in the famous Einstein formula: *E*= *mc*^{2. }

This equation is the essence of the nuclear energy, which is used in nuclear reactors all over the world for electricity generation, and is used, unfortunately, in Atomic bombs.

The famous equation of Einstein well fits to the Quantum mechanics (Quantum theory) which evolved along with the publishing of the Specific relativity theory. It is most interesting to note that, in spite of this, Einstein did not like the Quantum theory, for several reasons. We will not discuss this in this article.

Being based on very simple and known facts and ideas, and quite simple mathematics, the Special Relativity was quickly adopted by the scientist world, and also by regular people (this is noted here, as the General Relativity was not so acceptable).

It was the Special relativity, thus, that made Einstein a great celebrity all over the world.

****

The author holds B.Sc. degree in Electrical Engineering, M.Sc. degree in Interdisciplinary Engineering, and MBA degree. More about science and physics can be found at http://www.science.books4view.comand at www.physics.books4view.com