William Lawrence Bragg (31.03.1890-1.07.1971) was an English physicist and a Fellow of the Royal Society (1921). He was the son of W. H. Bragg. He was born in Adelaide (Australia). He graduated from Adelaide (1908) and Cambridge (1911) universities. In 1919 —37 he was professor at Manchester University, in 1937 — 38 director of the National Physical Laboratory, in 1938 — 53 professor and director of the Cavendish Laboratory, and in 1954—66 director of the Royal Institution.
His research was in the theory of X-ray diffraction, X-ray structural analysis, metallurgy, questions of polymorphism and of phase transitions in metals and alloys, protein chemistry and the history of physics. In 1912, independently of G. V. Wulff, he found the equation relating the wavelength of X-ray radiation to the period of the crystal lattice (the Bragg-Wulff formula), which underlies X-ray spectroscopy. He improved the methods of X-ray structural analysis, developed methods of deciphering complex crystal structures and determined the structures of many silicates. Using X-rays, in 1939 he obtained an optical image of the atomic structure of a crystal (the idea of the X-ray microscope). Bragg's X-ray microscope served as the starting point for the development of D. Gabor's ideas on the creation of holography. Together with J. Bernal and L. Pauling he laid the foundation of the structural analysis of proteins.
As head of the Cavendish Laboratory he fostered the development in the post-war years of new lines of research — radio astronomy and molecular biology.
Nobel Prize (1915). The D. Hughes Medal (1931), the Copley Medal (1966) and the Royal Medal (1946).