Recently, a student asked me, “What did Albert Einstein really do?” Well, here’s a Science Shorts version of what should actually be a long answer.

Einstein’s most famous equation is E= mc^{2}. This equation tells us that we can change mass into energy. The formula provides the basis of nuclear energy. The letter ‘E’ indicates the amount of energy, ‘m’ refers to the mass of an object, and the ‘c’ term is the speed of light squared. The c^{2} factor is so large that converting just a few atoms to energy can wipe out a city or run a power station.

There’s a lot more to relativity than E= mc^{2}. This equation is only a by-product of Einstein’s theory of relativity. Relativity revolutionized physics. It led us to understand that time and space are not absolute fixed quantities. They appear different to people moving at different speeds. However, because the speed difference is usually small, the disparity isn’t noticeable.

When asked the meaning of relativity, Einstein himself replied, “It was formally believed that if all the material things disappeared out of the universe, time and space would be left.” According to relativity theory, however, time and space disappear together with the things.

So next time someone asks you about Einstein, at least you won’t have to quickly change the subject!