9. The development of quantum theory (early 1900's)

In 1900, the German physicist Max Planck proposed a new scientific law that governed the absorption and emission of energy from matter. According to this law, energy is not continuous, but exists in small bits called quanta. Planck's discovery led to the development of the quantum theory of energy and eventually to a quantum theory for the atom. Practical applications of quantum theory led to the discovery of the laser and the transistor. Such applications also helped scientists understand the bonding within chemical compounds and how compounds interact with each other and with radiant energy.

 

Marianna A. Busch is the Chair and a Professor in the Department of Chemistry at Baylor University. Her Top 10 list centers on the most important scientific events of the 1900's. She discusses what these events meant to scientists and society in general. She calls attention to a number of the groundbreaking scientists who left their mark on the world of science in this century.

1.

The discovery of the molecular structure of DNA (1953)

2. The invention of the transistor (1947)
3. The first use of penicillin (1928)
4.

Development of the atomic bomb (1940's)

5. The launch of Sputnik I by the Soviet Union (Oct. 4, 1957)
6. Construction of the first laser (1960)
7. The development of new plants and the Green Revolution (mid-1900's)
8. The beginning of nuclear physics (early 1900's)
9. The development of quantum theory (early 1900's)
10. The publication of Silent Spring (1962)