Physics in Perspective

, Volume 13, Issue 1, pp 58–90 | Cite as

Bruno Rossi and the Racial Laws of Fascist Italy

  • Luisa Bonolis


Bruno Rossi (1905–1993), one of the giants of 20th-century physics, was a pioneer in cosmic-ray physics and virtually every other aspect of high-energy astrophysics. His scientific career began at the University of Florence in 1928 and continued at the University of Padua until 1938, when the Fascist anti-Semitic racial laws were passed in Italy. He was dismissed from his professorship and was forced to emigrate, as described in unpublished letters and documents that display the international character of physics and physicists. His young bride Nora Lombroso, his love of physics, and the solidarity of the physics community gave him the courage to begin a new life in Copenhagen, Manchester, and in the New World at the University of Chicago, Cornell University, Los Alamos, and after the Second World War at the Massachusetts Institute of Technology where he became the center of a worldwide research network.


Bruno Rossi Nora Lombroso Enrico Fermi Benito Mussolini Antonio Garbasso Sergio De Benedetti Walther Bothe Robert A. Millikan Arthur H. Compton Niels Bohr Hans A. Bethe Patrick M.S. Blackett Arcetri University of Florence University of Padua Niels Bohr Institute University of Manchester University of Chicago Cornell University Los Alamos Massachusetts Institute of Technology Fascism anti-Semitism racial laws Society for the Protection of Science and Learning Rossi coincidence circuit cosmic rays mesotrons X-ray astronomy solar wind internationalism of physics history of physics 



I dedicate my paper to the memory of Nora Lombroso Rossi, who always generously shared her personal views and recollections of past times with me, giving me invaluable insights into many episodes of her life with her husband Bruno Rossi. I thank Massimilla Baldo Ceolin and Daniele Amati for informative discussions on the effects of the racial laws in Italy. I am especially grateful to Linda Rossi for reading and commenting on a draft of my paper, and I am indebted to George W. Clark and Giuseppe Giuliani for valuable remarks on it. I thank Giovanna Blackett Bloor and John J. Compton for granting me permission to publish their fathers’ letters. I also am grateful to the staff of the MIT Institute Archives and Special Collections for their cordial and professional assistance and for granting me permission to publish portions of Bruno Rossi’s correspondence. Quotations from Carl D. Anderson’s and Patrick M.S. Blackett’s oral history interviews have been used by courtesy of the California Institute of Technology Archives and the American Institute of Physics Niels Bohr Library and Archives. My research was partially funded by the MIT Kavli Institute for Astrophysics and Space Research. Finally, I thank John S. Rigden for informative and valuable correspondence on various topics, and Roger H. Stuewer for his knowledgeable and helpful editorial work on my paper.


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Authors and Affiliations

  1. 1.RomeItaly

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