Short answers, pulled from the story.
Franco Modigliani received the 1985 Nobel Memorial Prize in Economics for his pioneering analyses of saving and of financial markets. His work on the life-cycle hypothesis and the Modigliani-Miller theorem were central to the award.
The Modigliani-Miller theorem, formulated in 1958 by Franco Modigliani and Merton Miller, argues that under certain assumptions the value of a firm is unaffected by whether it is financed through equity or debt. The theorem concludes that the debt-to-equity ratio is unimportant for private firms.
The life-cycle hypothesis, which Modigliani began developing in the 1950s, proposes that consumers aim for a stable level of consumption throughout their lifetime, saving during working years and spending those savings in retirement. It attempts to explain the overall level of saving in an economy.
Franco Modigliani taught at Columbia University and Bard College from 1942 to 1944, then joined the University of Illinois at Urbana-Champaign in 1948, followed by Carnegie Mellon University from 1952 to 1962. In 1962 he joined MIT as an Institute Professor, where he remained until his death in 2003.
In 1975, Modigliani and his former student Lucas Papademos introduced the NIRU, or non-inflationary rate of unemployment. The term describes a level of unemployment below which inflation begins to rise, and was framed as an improvement over the existing concept of the natural rate of unemployment.
Modigliani left Italy in 1938 following the passage of racial laws targeting Jewish people. He and his then-girlfriend Serena Calabi emigrated first to Paris, then to the United States in 1939, where he enrolled at the New School for Social Research.