1) John von Neumann (1903-1957) is at the top of the list. He is considered to be a natural genius, his parents did not force him to study and perform above average but they stimulated his interests and provided excellent tutors in math and the humanities. His contributions span not only math but also quantum theory, hydrodynamics, economy, and computer science. His mental abilities (calculations and memory) were awsome, perhaps nobody will ever achive his stunning performances. Also, he was a lively man enjoying parties and the good company of friends.

2) Enrico Fermi (1901-1954): definitely one of the greatest physicists of the 20-th century. It is said that Fermi was the last physicists that possessed extraordinary abilities both in theoretical and experimental physics. He was a master of clarity when solving difficult and complex problems. His name is attached to many scientific discoveries and concepts: Fermions (half-spin particles), Fermium (chemical element, Z=100), Fermi-Dirac statistics, Fermi golden rule, Fermi hole, etc. He received the 1938 Nobel Prize for Physics.

3) Among the massess, the name Albert Einstein (1879-1955) has become synonimous of genius. He could think for years on the same problem, this is how he discovered (developed) the theory of relativity. In the latter years of his life, while at the Institute of Advanced Studies (IAS) in Princeton he was searching an alternative approach to quantum theory and he became estranged with mainstream theoretical physics. He received the 1921 Nobel Prize for Physics.

4) Werner Heisenberg (1901-1976) is the father of Quantum Theory which he initiated while recovering from an attack of heyfeaver in the island of Heligoland. Given the pervasive presence of quantum theory in every electronic device, we can say that he made a giant leap forward. He received the 1932 Nobel Prize for Physics.

5) Erwin Schroedinger (1887-1961) is the founder of wave-mechanics, the alternative approach to matrix mechanics proposed by Heisenberg. The Schroedinger equation is one of the greatest achievements of theoretical physics, you can use it to describe the behavior and properties of microscopic matter (electrons, atoms, molecules, quantum dots, etc.). Together with Dirac he received the 1933 Nobel Prize for Physics.

6) Paul Adrian Maurice (PAM) Dirac (1902-1984) was a towering figure of theoretical physics. Soon after Heisenberg and Schroedinger, he developed transformation theory of quantum mechanics which culminated in the socalled Dirac equation which represents the basis of relativistic quantum theory. He predicted the existence of antimatter (or negative matter). Together with Schroedinger he received the 1933 Nobel Prize for Physics.

7) Richard (Dick) Feynman (1918-1988) was an enphant prodige. He developed an original version of quantum theory known as the path integral formulation of quantum theory. Togehter with Schwinger and Tomonaga he received the 1965 Nobel Prize for Physics.

8) Julian Schwinger (1918-1994), like Feynman, was a young prodigy. He developed the quantum action principle which represents a complementary approach to path integral quantum theory. Together with Feynman and Tomonaga he received the 1965 Nobel Prize for Physics.

9) Richard Bader (1937-2012) developed the Quantum Theory of Atoms in Molecules, QTAIM, which so far is the most powerful tool for the study of chemical bonding. It is a pity that some theoretical chemists do not understand or appreciate QTAIM, a very elegant theory based on the topological analysis of the experimental or theoretical electron density. Nevertheless, judging from the huge number of citations that Bader's QTAIM has received so far, we can say that the theory is becoming an irreplaceable instrument for researchers in the fields chemistry and molecular physics.

10) Wolfgang Pauli (1900-1958) was an enphant prodige who mastered the theory of relativity at the age of twenty. He is known for his contributions to quantum mechanics, particularly the Pauli exclusion principle. He received the 1945 Nobel Prize for Physics. He seem having been quite arrogant; legend tells that when Paul Ehrenfest, a Dutch physicist, met Pauli the first time, he said gI like your work more than I like you, only for Pauli to shoot back: With me, it is the other way round.h