Isidor Isaac Rabi was born on July 29th, 1898, to an orthodox Jewish family in Galicia, Northeastern Austria-Hungary. The town of Rymanów, sometimes shared with Ukraine, belongs to Poland these days (it's about 20 km from the Slovak borders). He died of cancer (after doctors would monitor him via magnetic resonance imaging) in New York about 25 years ago, in 1988.
Soon after he was born, his family moved to the New York City where his dad ran a grocery store in Brooklyn. Books about heliocentrism turned Izzy into an atheist. He asked: "Who ordered God?" if I improve his question a little bit. His compromise with the parents involved a lecture on the electric light he gave during a ceremony that turns 13-year-old Jewish boys into adults.
He would build his own radio as a kid; attended a manual training high school; entered Cornell to study engineering; quickly switched to chemistry (he would investigate oxidation states of manganese) and the Cornell's student army training corps. Jobs weren't quite ready for Jews at that time so he would briefly work in a lab and then as a bookkeeper.
In 1922, he would return to Cornell as a chemistry student and would gradually be converted to a topic that wasn't interesting for him, magnetism – he got a "magnetically susceptible" job at the City College of New York in 1924 (the research involved torsion balances and crystals, too). Needless to say, magnetism is also what earned him the 1944 Physics Nobel Prize for the magnetic nuclear resonance.
Since 1927, he would be spending years in Europe and got familiar with the big shots of the quantum revolutionary generation. He would later teach at Columbia (Norman Ramsey agreed with everyone else that Rabi was the worst teacher ever), work for the Manhattan Project, on radars and radiation during the war, for the Atomic Energy Commission, as a science adviser to Dwight Eisenhower, in Brookhaven labs, and for UNESCO where he participated in the conception of CERN. In the 1930s, he welcomed the discovery of the muon by the famous sentence "Who ordered that?"
Despite his bad teaching skills and his weak publication record, the early 1930s would already see Rabi as an important enough researcher in quantum mechanics, especially in topics related to resonances. He was intrigued by the Stern-Gerlach experiment and realized that the same mechanism probably affected the nuclear spins and not just the atomic ones. It still took him years to develop NMR – whose importance not only in medicine seems self-evident today. The Rabi problem and the Rabi cycle show his focus on the near-resonance evolution of two-level and several-level systems in quantum mechanics – analyses that are applicable not only to nuclear spins.
Incidentally, tomorrow, on July 30th, we will remember the 150th anniversary of the birth of Henry Ford, the greatest 20th century carmaker who was able to change a luxurious line of products to a part of everyday people's everyday lives. His total wealth is sometimes converted to $188 billion of present dollars – pi times Bill Gates. He would struggle to spread consumerism and therefore peace throughout the world – if you allow me to overlook his antisemitic ideas.