In this blog post, I want to share a little bit about my fascination with one of the most beautiful minds of the past century namely that of Albert Einstein and about his famous equation:
In the year 1999, just when the century ended, the Times Magazine asked for nominations for the ‘Person of the Century’ award. And as you can imagine there were hundreds of nominations made and they had a tough time to decide over the finalists. Three finalists were shortlisted, first one was Franklin Roosevelt for ‘triumph of freedom over fascism and communism’, and the second finalist was Mahatma Gandhi as the ‘embodiment of human rights and his faith in non-violence’. But the person who was chosen as the person of the century award was Albert Einstein. About him, scientist and author Fredric Golden wrote,
Einstein was a pre-eminent scientist in a century dominated by science. The touchstones of the era, the atomic bomb, the big bang, quantum physics, and electronics all bear his imprint. He was the embodiment of pure intellect. He was unfathomably profound- the genius among geniuses who discovered merely by thinking about it that the universe was not as it seemed.
Although he was a genius among geniuses, he did very well in college but he had a great difficulty in finding a teaching job in a school. And therefore after a large number of unsuccessful attempts, he was able to find it. It’s a lesson for all of us that failures do not matter and we have to keep trying. Eventually in 1905, when Einstein was 26 years old and was working in total isolation (not in a university or in a research laboratory) but in a Swiss patent office all by himself he published five outstanding papers. These papers are often referred to as ‘Annus Mirabilis’ Papers. These are Latin words which means ‘miraculous here’. Therefore, the year 1905 is known as Einstein’s year of miracles.
Another fun fact I want to share here is that the year 1666 was the year of miracles for Isaac Newton. The University of Cambridge was closed down because of the plague in the United Kingdom and Newton was sent home. There in total isolation he wrote down the Laws of Planetary Motion, he worked out in the theory of Optics, and he also introduced the theory of Calculus.
In the five papers he published, the first one was a new method for determination of molecular dimensions, for example, determining the size of a water molecule. In the second paper, and this was quite revolutionary in nature, he said that the radiation or light can be emitted or absorbed in only discrete amounts called quanta or packets of energy. And the value of the energy was proportional to the frequency of the radiation that is emitted. And these quanta are now known as photons. This was a revolutionary theory because this theory eventually led to what is known as wave-particle duality and the development of Quantum theory. In his 3rd paper Einstein talked about Brownian motion and in his 4th paper he put forward the special theory of relativity which implied that the time is not absolute. And in the 5th paper, he introduced the famous equation:
This equation implies the equivalence of mass and energy and that the mass can be converted to energy and vice versa. But even though it might be the famous equation in the world, but what you might not know is that it isn’t the whole equation. It just describes the object that has mass and that isn’t moving. The full equation is:
E2 = (mc2)2 + (pc)2
Where p represents the momentum of an object in question, C is the velocity of light, m is mass of the object and E is energy.
So, from here it’s clear to see that the object that isn’t moving and thus doesn’t have any momentum, therefore p is zero. So, we get back our old equation E= MC2. On the other hand, if the particle is in question is mass-less, then the mass is zero and we get
This tells us that the energy of a mass-less particle like the photon of light is the same as its momentum (up to a factor as the speed of light). In fact, the closer the energy of something to ‘p’ times ‘c’, the closer that something is to behaving like light.
Einstein has a magical talent where he could take a hard physical problem and boil it down to the powerful visual image or the thought experiment which is quite popularised in the popular TV sitcoms like The Big Bang theory.
The seeds of Einstein’s key thoughts were planted when he was just a child. He grew up in a small house in Munich in Southern Germany. His unique personality was evident early on. Like many innovators, Einstein was a rebel, a loner but deeply curious. He was slow in learning and speaking as a child, so slow that his parents had to consult a doctor. He was a daydreamer but deeply persistent.
Since childhood, Einstein was gripped by a desire to understand the underlying laws of nature. The most important thing that you can learn from Einstein is just the power of an idea. It’s extremely encouraging that had such a pure thought to solve the riddle of the universe. There are only a few moments in science history where we have to completely rethink our picture of the world that we live in and with Einstein’s theory we had these moments.