Richard Feynman was born in New York in 1918. He studied physics at the Massachusetts Institute of Technology. In 1942 he was awarded a doctorate from Princeton University and joined the team of scientists engaged in the development of the atomic bomb at Los Alamos. He taught at Cornell University and the California Institute of Technology and in 1954 He was elected to the American Academy of Science.
In 1965, Richard Feynman was awarded the Nobel prize in physics, together with Julian Schwinger and Sin-Itiro Tomonaga, for the development of a quantum electrodynamics theory.
In classical physics, electrodynamics was an established theory, but in the modern quantum physics, difficulties were encountered in its development until the turning point discovered by Feynman was reached.
Feynman’s calculative approach, with the help of which he succeeded in constructing the quantum electrodynamics theory, holds that in order to calculate the likelihood of a particle moving from a certain initial position to a certain final position, the probabilities must be calculated for every possible path separately, and the probabilities of all possible paths must be summarized. This method is known as “Feynman’s integrals”. He described the various paths with the help of the famous “Feynman’s diagrams” which simplified comprehension of the abstract processes and enabled, with the help of calculations he determined, the explanation of phenomenon that did not fit in with earlier calculations of the quantum theory.
Apart from being a brilliant scholar, Feynman was also famous for his talents as a drummer and for his special sense of humor. When he was working in Los Alamos, he would break into the safes in which top-secret material was kept and leave a note for the security officers with the message, “Guess who did it?” His books are written in a light style and with a great deal of humor, and achieved wide popularity.
Richard Feynman died in 1988.
Francois Jacob was born in Nancy, France, in 1920 in a family of merchant. His medical studies in the Paris University came to an end in 1940 with the invasion of France by the Germans; Jacob joined the “Free French” and served as a medical officer. His hands were severely wounded; so he understood he will never realized his dream to become a surgeon.
In 1947, he received his medical degree at the Sorbonne and devoted his doctoral research to the genetics of bacteria. He started working at the Pasteur Institute and in 1960 he was nominated director of the Genetics Research Department.
In 1965, Francois Jacob was awarded, together with Lwoff and Monod, the Nobel prize of physiology and medicine “for their discoveries concerning genetic control of enzyme and virus synthesis”.
Jacob and Monod discovered the messenger-RNA molecule which transmit the information encoded in the DNA loaded in the cell nucleus – from the nucleus to the cell cytoplasm. There, with the help, among others, of two RNA, a new protein molecule is manufactured which fits exactly the code initially inscribed on the DNA.
Furthermore, Jacob and Monod differentiated two types of genes: the structural genes which are bearing all characters and information of a cell; and the regulatory genes which influence the rate of expression of each one of the structural genes. The regulatory genes can be influenced by internal stimuli of various sorts and, also occasionally, by external factors such as heat, radiation, and so on. Thus can explain diverse phenomenon such as burst of certain cancerous tumors and the sudden outbreak of viral diseases such as Herpes and Aids.
Julian Schwinger was born in 1918 in the United States.
He received the 1965 Nobel prize in physics, together with Richard Feynman and Sin-Itiro Tomonaga, “for their fundamental work in quantum electrodynamics”, which had a profound influence on the physics of elementary particles.
Julian Schwinger passed away in 1994.