Felix Bloch

Felix Bloch (23 October 1905 – 10 September 1983) was a Swiss-born American theoretical physicist best known for developing the nuclear magnetic resonance (NMR) method, a technique for measuring nuclear magnetic moments that laid the groundwork for magnetic resonance imaging (MRI) and earned him the 1952 Nobel Prize in Physics, shared with Edward Mills Purcell. Born in Zurich to Jewish parents, Bloch attended public schools and Gymnasium there before studying engineering and then physics at the Eidgenössische Technische Hochschule (ETH) Zurich from 1924 to 1927, earning his Ph.D. in 1928 from the University of Leipzig under Werner Heisenberg with a thesis on the quantum mechanics of electrons in crystal lattices, introducing Bloch's theorem which describes electron wavefunctions in periodic potentials. Early in his career, Bloch contributed to solid-state physics, including theories of ferromagnetism and metallic conduction, and worked with leading physicists like Wolfgang Pauli, Hendrik Kramers, Niels Bohr, and Enrico Fermi across institutions in Zurich, Utrecht, Leipzig, Copenhagen, and Rome. Emigrating to the United States in 1933 amid rising Nazism, he joined Stanford University in 1934 as its first professor of theoretical physics, where he later measured the neutron's magnetic moment with Luis Alvarez in 1939 and pioneered nuclear induction experiments in 1946 with William Hansen and Martin Packard, demonstrating NMR in liquids. Bloch served as the inaugural Director-General of CERN in 1954, fostering its early development before returning to Stanford, where he continued research on superconductivity and low-temperature physics until retirement in 1971, holding the Max Stein Professorship from 1961.

Felix Bloch was born on October 23, 1905, in Zurich, Switzerland, to Jewish parents Gustav Bloch and Agnes Bloch (née Mayer). His father worked as a wholesale grain dealer in the city, while his mother hailed from Vienna and was a cousin of Gustav. The family resided in Zurich, where Bloch grew up in a middle-class Jewish household amid Switzerland's stable early 20th-century environment.

From 1912 to 1918, Bloch attended the Kantonsschule in Zurich, a secondary school emphasizing classical education. Recognizing his early aptitude for mathematics, his parents enrolled him in the Realgymnasium in Zurich, a institution focused on scientific and mathematical training, from which he graduated in spring 1924. These formative years fostered his interest in quantitative sciences, though specific childhood anecdotes beyond academic promise remain sparsely documented in primary records. Bloch's upbringing reflected the assimilated Jewish mercantile culture of urban Switzerland, unmarred by overt religious orthodoxy but shaped by familial expectations of intellectual pursuit.

Bloch was born on October 23, 1905, in Zurich, Switzerland, to Jewish parents Gustav Bloch, a businessman, and Agnes Bloch (née Meyer). On March 14, 1940, he married Lore Clara Misch (1911–1996), a physicist who specialized in X-ray crystallography and whom he met while both were émigrés in the United States. The couple had four children: twin sons born in 1941, another son in 1945, and a daughter.