**1) Dirac, Paul Adrien Maurice** pronounced dih RAK, (1902-1984), a British theoretical physicist, became noted for his mathematical equation describing the behavior of the electron. Dirac also demonstrated the fundamental unity of the two forms of quantum mechanics, wave mechanics and matrix mechanics. He shared the 1933 Nobel Prize in physics with the Austrian physicist Erwin Schrodinger for his equation and his other contributions to quantum mechanics.

Dirac introduced his equation, now called the Dirac equation, in 1928. It accounts theoretically for the spin of an electron and for other aspects of the particle's behavior. Dirac's theory also predicted that the negatively charged electron should have an antiparticle-a positively charged electron. The American physicist Carl D. Anderson detected this positively charged electron-the positron-in 1932.

Dirac was born in Bristol, England, on Aug. 8, 1902. He attended Bristol and Cambridge universities. From 1932 to 1969, he held the Lucasian Professorship of Mathematics at Cambridge, a chair once held by the great English scientist Sir Isaac Newton. In 1971, Dirac became a professor of physics at Florida State University. His book The Principles of Quantum Mechanics (1930) is a classic in its field. Dirac died on Oct. 20, 1984, in Tallahassee, Florida.

**Contributor: **Roger H. Stuewer, Ph.D., Professor of the History of Science and Technology, University of Minnesota.

**2) Schrodinger, Erwin** pronounced SHRAY dihng uhr, (1887-1961), an Austrian theoretical physicist, became known for his mathematical equation describing the wavelike behavior of electrons. Schrodinger shared the 1933 Nobel Prize for physics with the British physicist Paul Dirac for this work and for his other contributions to atomic theory.

Schrodinger developed his equation, now known as the "Schrodinger equation," in 1925 and introduced it in 1926. He based it on the ideas of Louis V. de Broglie, a French physicist, who in 1924 had proposed a theory that electrons behave like waves. The Schrodinger equation became the basis of a version of a field of physics called quantum mechanics.

In later years, Schrodinger concentrated on expanding Albert Einstein's theory of gravitation to include electrical and magnetic phenomena. Schrodinger was also interested in the impact of science and technology on philosophy. His short book What Is Life? and Other Scientific Essays (1956) details his concerns.

Schrodinger was born on Aug. 12, 1887, in Vienna. He served as a professor of theoretical physics in several German and Swiss universities. He also was associated with the Dublin Institute for Advanced Studies.

**Contributor:** Richard L. Hilt, Ph.D., Professor of Physics, Colorado College.

## 0 comments:

## Post a Comment