In 1928, Paul Dirac created an equation that showed a universe alien to our intuitions everyday. The British physicist, at only 25 years old, presented his theory of the electron, an attempt to harmonize the quantum world with the theory of Einstein's special relativity and explain the behavior of these particles at high speed. The formula, instead of including two characteristics of the electron, the spin that determines whether it spins clockwise or counterclockwise, contained four. If this equation described reality, and for Dirac his mathematical beauty proved that it did, it was necessary that another type of electrons existed in the world, identical to the known ones, but with a positive charge.
