Enrico Fermi – one of the great physicists of the 20th century – was a beacon for every Italian student of physics including myself. This sentiment is wonderfully captured in The Pope of Physics by Gino Segrè and Bettina Hoerlin, as they explain how Fermi’s colleagues bequeathed him with the title of “Pope”, thanks to his ability of using “the simplest of means [to] estimate the magnitude of any physical phenomena”. With their book, Segrè and Hoerlin present the first, long-awaited, English-language biography of one of the most creative and hard-working scientists of recent times.

Fermi is no stranger to both Segrè – a professor of physics and astronomy at the University of Pennsylvania, US – and his wife Hoerlin – teacher, health commissioner and author of Steps of Courage: My Parents’ Journey from Nazi Germany to America. That is because Segrè’s uncle was the Nobel-prize-winning physicist Emilio Segrè, who happened to be Fermi’s first student in Rome. The two families always maintained their friendship, even after they were forced to flee to the US in 1939 to escape Mussolini’s antisemitic regime – the Segrè family and Fermi’s wife, Laura, were Jewish. This long-standing relationship with relatives and close friends of the Fermi family helped Segrè and Hoerlin write about Fermi – who was once described by an Italian peer as a physicist with a capital F (the Italian for physicist being fisico).

The book opens with a depiction of Fermi’s early life, delving into his family roots and in particular, the deep bond he shared with his brother Giulio, who died prematurely. Written against the background of Italy in the early 1900s, these chapters leave the reader with a feeling of nostalgia for the “good old days”. The authors describe Fermi’s education and how his interest – or more aptly, his love – for physics blossomed, before going into Fermi’s time at the Sapienza University of Rome, where he spent his days nurturing his passion for hands-on work and his friendship with Franco Rasetti and Enrico Persico. This was the period during which Fermi began to immerse himself in the then new and revolutionary field of quantum physics.

The reader follows Fermi on his travels to Göttingen in Germany and Leiden in the Netherlands – where he spent a year interacting with some of the most famous scientists of the day, including Albert Einstein. The authors also talk about the exciting time during which Fermi worked with a group of talented young scientists – know colloquially as the Via Panisperna boys. Reading about these years, it becomes obvious that Fermi was a key driver in the advancement of quantum mechanics, from mathematical abstraction to experiment. His crucial contributions include helping build a clearer picture of the atom and explaining beta decay – the work that won him a Nobel prize in 1938 and provided the foundations for nuclear physics.

In parallel, the reader also learns about his personal story with his wife-to-be Laura, the not-so-warm relationship with his two children, along with the dangerous turn taken by politics in Italy. Fermi lived through a period of great changes due to the rise of Fascism, and the book reproduces the forboding atmosphere of the time quite remarkably. It describes how Fermi and his family did not return to Italy in 1938, after picking up the Nobel prize in Stockholm. The family’s story was similar to that of many other Jewish scientists at the time. Despite the fact that Fermi never took a public stand against Mussolini’s regime, he attempted to help his Jewish friends while preparing to leave for Columbia University in New York. The tension of those tumultuous times, which many of us have only heard of, is felt by the reader and it is a relief when the Fermis arrive safely in the US.

From here onwards, The Pope of Physics tells the story of the scientific discoveries leading up to the Manhattan Project. Although widely known, it is still surprising to read that the world’s first functioning nuclear pile was built under an abandoned football stadium. At the end of the war, the project was replaced by the Atomic Energy Commission and Fermi served on its influential general advisory committee – chaired by Robert Oppenheimer – while continuing his studies.

Although Fermi’s discoveries deeply advanced knowledge in many fields of physics – and made giant leaps for example in medical physics – his work formed the basis of one of the darkest creations of human knowledge: the atomic bomb. The book discusses this, and recounts how Fermi was among the first to warn military leaders about the potential negative impact of nuclear energy. Toward the end of his life, Fermi questioned his faith in society at large and its ability to make wise choices about nuclear technology.

The story ends with the last month of Fermi’s life – he died of stomach cancer at the age of 53. In the same rational way in which he looked at nature, he also looked at the end of his passage in this world. The final pages, describing his last conversations with friends and colleagues, are moving and show his great steadiness and dignity.

I thoroughly enjoyed this well-written book, which captures the lively life and times of Fermi. The book depicts what a truly a fascinating figure Fermi was, in an attention-grabbing manner. The reader enjoys a journey through the major physics discoveries of the time, which are placed in the proper historical context. Fermi’s achievements are covered in a way that is certainly satisfactory for a more scientifically inclined reader, but still comprehensible for a casual reader. If you’re interested in the history of science, and the story of someone who could be thought of as the most famous Italian scientist since Galileo Galilei, The Pope of Physics is the book for you.