The Bragg–Gray cavity theory developed by Louis Harold Gray, William Henry Bragg, and a physicist that was a joint winner of the Nobel Prize in Physics in what year?
Bragg–Gray cavity theory:  It was developed in 1936 by British scientists Louis Harold Gray, William Henry Bragg, and William Lawrence Bragg. William Lawrence Bragg:  He was joint winner (with his father, William Henry Bragg) of the Nobel Prize in Physics in 1915: ""For their services in the analysis of crystal structure by means of X-ray"", an important step in the development of X-ray crystallography.
1915