Niels Bohr is the father of quantum theory and one of the most renowned physicists in history. Niels Bohr’s work concentrated on atoms and electrons, he realized that since its creation no one had tried to explain why the Mendeleev’s periodic table worked the way it did. Bohr found that electrons occupy space around atoms similar to the orbits of planets around stars and they exist in ‘shells’ and that they ‘leap’ to opposite states periodically. He also noticed that there was a correlation between the number of electrons in an atom and the complexity they exhibit.
This was the birth of quantum physics and caused quite a stir in the world of science. To explain the invisible particles present in reactions and experiments Bohr coined the term ‘quanton’ which is explained by his principle of complementarity. Prominent scientists of the time including Albert Einstein were not happy with Bohr’s explanation of quantum physics and they even debated the subject rather heatedly. During World War II however they both campaigned for global disarmament and befriended each other in the USA.