Albert Einstein is rightly acknowledged as the 20th century’s greatest scientist. It’s more difficult to suggest who’s in the group of theoretical physicists sitting just below Einstein in terms of greatness.
That list would reasonably include Niels Bohr, Madame Curie, Erwin Schrödinger, Werner Heisenberg, Enrico Fermi, and Paul Dirac. You probably should have heard of Bohr, Curie, Heisenberg, Schrodinger, and Fermi, but of Paul Dirac I imagine you might not have recognised the name. [Click on image to expand].
Paul Dirac [1902-1984] was an English theoretical physicist, who, among his contributions to quantum mechanics, proved the existence of anti-matter based purely on mathematical calculation. Tim Radford writes in his Guardian article about Graham Farmelo’s biography of Dirac in, Paul Dirac: The man who conjured laws of nature from pure thought.
Dirac was among the world’s leading physicists at the October 1927 Fifth Solvay International Conference on Electrons and Photons, where the world’s most notable physicists met to discuss the newly formulated quantum theory. See photo and the names of the delegates below.