Commonly known stalwarts of quantam physics : seers of existence of wave and particle nature for all materials but since physics at a stage(19th century) was considering with light and other subtle matter(like optics, diffracion, interference, polarization), the predominant observation was only of the matters wave nature, but Max Planck in 1900 introduced the term 'quantum' for particle nature of the matter(for him he was dealing with blackbody radiation waves) and Einstein in 1905 introduced the term photon for light quantum(particle of light) as he was dealing with photoelectric effect of electrons emitting from conductor surface when photons come in contact with it. Wave & particle nature of matter was 'formally' unified into a single theory by Neils Bohr in 1912 while he observed and explained the Hydrogen spectrum. Earlier: 1. Maxplanck 2. Einstein 3. Neils Bohr Later, 1. Louis de Broglie in 1924: more grosser particles also has wave nature similar to subt...