Felix Bloch was a Swiss-born American physicist who shared the 1952 Nobel Prize in Physics with Edward Purcell for a method for determining the magnetic fields of neutrons in atomic nuclei. This was developed into the nuclear magnetic resonance (NMR) method of determining chemical structures.

From 1934 Bloch was professor of theoretical physics at Stanford University in California. He was the first director (1954–1955) of Conseil Européen pour la Recherche Nucléaire (CERN), the European center in Geneva for research in high-energy particle physics.